Skip to content

BLOG
LATEST NEWS
CONTACT US
FAQ
Newsletter
Sign up for Newsletter
Signup for our newsletter to get notified about sales and new products. Add any text here or remove it.

Water Treatment
Spares & Parts
Media & Consumables
Services

Basket / £0.00 0
- No products in the basket.
  
  Return to shop

0

Basket

No products in the basket.

Return to shop

Search for:

Login / Register
CONTACT
- 08:00 - 17:00
- 01629 363311

- 08:00 - 17:00
- 01629 363311

Drop Test Kits

Home / Shop / Drop Test Kits

Chlorine Dioxide VLR – Range 0 – 12 ppm

£149.90 - £179.88 (inc. VAT)

To request a call back regarding this product please complete the form below.

Product Name

Product Name

Chlorine Dioxide VLR - Range 0 - 12 ppm quantity

SKU: S36-DTK011

Browse

10 Big Blue Filter Housing
10 Clear Double Filter Housing
10 Clear Triple Filter Housing
10 Hot Water Filter Housing
10" Big Blue Double Filter Housing
10" Big Blue Triple Filter Housing
10" Single Blue Filter Housing
10″ Bacteria Resistant Filter Housing
10″ Clear Water Filter Housing
12v UV Water Filters
20 Big Blue Double
20 Big Blue Filter Housing
20 Big Blue Triple
20" Water Filter Housing
4” x 20” cartridge filters
40" RO Membrane Housing ABS End Caps
520 Series Valve
ABS Double Union Ball Valves
Activated Carbon
Activated Carbon 10" x 2.5"
Activated Carbon 10" x 4"
Activated Carbon Cartridge Filter
Activated Carbon Filter 20" x 2.5"
Activated Carbon Filters 20" x 4"
Adaptors Plugs Nylon
Air Compressors
Air Filters
Air Hose Assemblies
Airline Tubing and Hoses
Alkalinity
Ammonia
Anthracite
Antibacterial Cartridge Filters
Antiscalant Chemicals
Aquamatic 4 Series Spares
Aquamatic 4 Series Valve
Aquamatic 521 Series Spares
Aquamatic 524 Series Spares
Aquamatic 526 RA Series Spares
Aquamatic 526 RF Series Spares
Aquamatic 534 RV Series Spares
Aquamatic 535 RAE Series Spares
Aquamatic 535 RF Series Spares
Aquamatic 537 RAE Series Spares
Aquamatic 537 RF Series Spares
Aquamatic Ejectors
ARC for Chlorine Removal
ARC for Chlorine Removal Exchange
Atlas H Range UV Water Filters
Atlas L Range UV Water Filters
Autotrol Duplex 1"
Autotrol Duplex 2"
Autotrol Duplex 3/4"
Autotrol Simplex 1" Time Controlled
Autotrol Simplex 1″ Meter Controlled
Autotrol Simplex 2" Meter Controlled
Autotrol Simplex 2" Time Controlled
Autotrol Simplex 3/4" Meter Controlled
Autotrol Simplex 3/4" Time Controlled
Autotrol Valves Training Course
Baffled Tanks
Bag Filter Housing Range 81
Bag Filters for Plastic Housings
Ball Check Valve - Flanged PN10
Ball Check Valves – Standard Ball BSPP
Basket Strainers
Bayoxide
BC Range Natural Bone Charcoal
BC Range Natural Bone Charcoal Exchange
Beta Composite
Big Bubba Filter Housings
Birm
Bone Char
Booster Pump with Tank up to 1000 ltr
Booster Pump with Tank up to 10000 ltr
Booster Pump with Tank up to 1500 ltr
Booster Pump with Tank up to 2000 ltr
Booster Pump with Tank up to 2500 ltr
Booster Pump with Tank up to 3000 ltr
Booster Pump with Tank up to 3500 ltr
Booster Pump with Tank up to 4000 ltr
Booster Pump with Tank up to 5000 ltr
Booster Pump with Tank up to 6000 ltr
Booster Pump with Tank up to 7000 ltr
Booster Pump with Tank up to 8000 ltr
Booster Pump with Tank up to 9000 ltr
Brass Adaptors Plugs Manifolds
Brass Ball Valves
Brass Check Valve - Wafer Spring
Brass Check Valve – Spring Check Valve
Brass Check Valve Spring Check Acetal Disc
Brass Check Valve Spring Check Male x Female
Brass Check Valve Spring Check Metal Disc
Brass Check Valves - Swing Check Metal Seat
Brass Check Valves Spring Check Female x Male
Brass Check Valves Swing Check Rubber Seat
Brass Fittings
Brass Float Valve
Brass Foot Valve + Strainer
Brass Hosetails
Brass Solenoid Valves
Brass Spring Check Valves
Brass Y Type Strainer
Break Tank Booster Pump
Brine Tanks
Bromine
Bronze Check Valve - Horizontal Lift Valve – PN32
Bronze Check Valve - Swing Check Valve PN25
Bronze Check Valve - Swing Check Valve PN25 NPT
Bronze Check Valve - Vertical Lift
Bronze Check Valve Flanged PN16
Bronze Check Valve PN25 NPT
Bronze Check Valve Wafer Spring
Bronze Pressure Reducing Valves
Bronze Y Strainer
Bronze Y Strainer Flanged PN16
BSP Adaptors
Bund Tanks
Carbon Block Cartridge Filters
Carbon Block Cartridge Filters 10" x 2.5"
Carbon Block Cartridge Filters 10" x 4"
Carbon Block Filters 20" x 2.5"
Carbon Block Filters 20" x 4"
Carbon Steel Butterfly Valve
Cast Iron Knife Gate Valves
CAT 5 Break Tanks - Rectangular
CAT 5 Equilibrium Drop Arm Float Valves
CAT 5 Type AB Air Gap
Challenger 25 Slide Incubator
Check Valves
Chemicals
Chemicals - Flocculants
Chloride
Chlorine
Chromium
Cintropur 10000 Spares
Cintropur 10000 UV Spares
Cintropur 2000 UV Spares
Cintropur 2100 Spares
Cintropur 2100 UV Spares
Cintropur Activated Carbon
Cintropur Domestic Range
Cintropur Duo UV Spares
Cintropur Filter Spares
Cintropur Industrial Range
Cintropur Light Industrial Range
Cintropur NW25 Filter Sleeves
Cintropur NW25 Filter Spares
Cintropur NW25 Replacement Filters
Cintropur NW280 Filter Sleeves
Cintropur NW32 Filter Spares
Cintropur NW340 Filter Sleeves
Cintropur NW400 Filter Sleeves
Cintropur NW650 Filter Spares
Cintropur NW800 Filter Spares
Cintropur Replacement Filters
Cintropur Replacement NW32 Filters
Cintropur SL Range Spares
Cintropur SL160
Cintropur SL160 Filter Sleeves
Cintropur SL240
Cintropur SL240 Filter Sleeves
Cintropur Smart Line Range
Cintropur TIO
Cintropur TIO UV Spares
Cintropur UV Filters
Cintropur UV Spares
Cintropur UV Water Filters
Clack 3 Inch Spares Accessories
Clack Birm Water Filter Meter Controlled
Clack Carbon Water Filter
Clack Duplex Nitrate Reduction Filters
Clack Filox R Water Filter Meter Controlled
Clack Hydrogen Sulphide Water Filter
Clack Nitrate Reduction Water Filter
Clack Organic Scavenger Water Filter
Clack pH Water Filter
Clack Sand Water Filter Meter Controlled
Clack Turbidex Water Filter Meter Controlled
Clack Valves Training Course
Clack Water Softener - WS1 CI
Clack Water Softener - WS2
Clack Water Softener - WS3
Clack Water Softener WS 1.5
Clack Water Softener WS1.25
Clack WS 1.25CI
Clack WS1 TT Duplex Water Softener
Clack WS1 Valve Spares
Clack WS1.25 Duplex Water Softener
Clack WS1.25 Valve Spares
Clack WS1.5 CI
Clack WS1.5 Duplex Water Softener
CLACK WS1.5 VALVE SPARES
Clack WS1CI
Clack WS1TC
Clack WS2 CI
Clack WS2 Duplex Water Softener
Clack WS2 Valve Spares
Clack WS3
Clack WS3 Duplex Water Softener
Cleaning Chemicals
Clothing
- Hoodies
Colour of Water
Combination Meters
Compact Non Electric RO Spares
Compact Reverse Osmosis Stand
Comparator Test Kit
Conductivity Controllers – CC3020
Cone Storage Tanks
Conference Room
Cooling Tower Controller – AS3020
Cooling Tower Controller – AS3050/51
Copper
Cryptosporidium Candles
Cryptosporidium Cartridge Filters
Cryptosporidium Filter Housings Multi
Cryptosporidium Filter Housings Single
Crystal Right
Cultura 18 Slide Incubator
Demineralisation Controllers – ES2070CA
Demineralisation Training Course
DI Vessels with Hubs
Dipslides
Discovery 8 Slide Incubator
Dissolved Oxygen Meters
Domestic Scale Inhibitors
Domestic Traditional Range RO Spares
Dosing Pumps
Dosing Tanks
Dosing Tanks and Bunds
Double Plate Check Valve - NBR Seat
Double Plate Check Valve – EPDM Seat
Double Plate Check Valve Multi Flange
Dow 4" Membranes
Dow 4" Seawater Membranes
Dow 8" Membranes
Dow 8" Seawater Membranes
DOW Residential Membranes
Drop Test Kits
Drop Test Reagents
DS Range
Ductile Iron Butterfly Valve
Filox R
Filter AG+
Filter Gravel
Filter One Cartridge Filters
Filter Sand
Fleck 2750 Service Kit
Fleck 2850 Service Kit
Fleck 2900 Service Kit
Fleck 3150 Service Kit
Fleck 3900 Service Kit
Fleck 5600 SE Service Kit
Fleck 5600 Service Kit
Fleck 9000 Service Kit
Fleck 9500 Service Kit
Fleck Duplex 2910 ES
Fleck Duplex 2910 NXT
Fleck Duplex 3900 NXT
Fleck Duplex 9000
Fleck Duplex 9100 SXT
Fleck Duplex 9500 SXT
Fleck Simplex 2750 Meter Controlled
Fleck Simplex 2750 Time Clock
Fleck Simplex 2850 Meter Controlled
Fleck Simplex 2850 Time Clock
Fleck Simplex 2910 Meter Controlled
Fleck Simplex 2910 Time Clock
Fleck Simplex 3900 Meter Controlled
Fleck Simplex 3900 Time Clock
Fleck Simplex 5600 Meter Controlled
Fleck Simplex 5600 Time Clock
Fleck Simplex Activated Carbon
Fleck Simplex Birm
Fleck Simplex Filox R
Fleck Simplex Multimedia
Fleck Simplex pH Correction
Fleck Simplex Turbidex
Fleck Valves Spares
Fleck Valves Training Course
Float for float valve
Fluoride
Food Grade Legris Fittings
Forged Steel Check Valve – BSP
Forged Steel Check Valve – NPT
Forged Steel Check Valve – Socket Weld
Framed CAT 5 Break Tanks
Framed Tanks
Free Chlorine
Garnet
Genesol 34
Gnat 2 Dipslide Incubator
Hand Pumps
Handwheel Knife Gate Valves
High Flow Plastic Filter Housings
Horizontal Storage Tanks
Hose Clips Clamps Accessories
Hose Reels
Hot Water Cartridge Filters
Hydranautics 2 1/2" Membranes
Hydranautics 4" Membranes
Hydranautics 8" Membranes
Hydranautics CPA Membranes
Hydranautics ESNA Membranes
Hydranautics LFC Membranes
Hydranautics SWC Membranes
Industrial Bund Tanks
Industrial Scale Inhibitors
Industrial Storage Tanks
Inline TDS Meter
Iodine
Ion Exchange Resin
Ion Exchange Resins Training Course
Iron
Iron Check Valve - Ductile Iron Lever & Weight
Iron Check Valve - Ductile Iron PN16
Iron Check Valve - Flanged PN16 - EPDM
Iron Check Valve - Flanged PN16 Lever & Weight
Iron Pressure Reducing Valves
Iron Reduction Cartridge Filter 10" x 2.5"
Iron Removal Cartridge Filter
Iron Removal Cartridge Filters 10" x 4"
IWE 38 Acidic Membrane Cleaner
IWE 40 Alkaline Cleaner
IWE Brackish Water Membrane
IWE Brackish Water Membrane 40"
IWE Brackish Water Membrane 8" x 40"
IWE Low Flow Reverse Osmosis Membranes
IWE Mixed Bed Resin
IWE UV Water Filters
IWE Water Softener Resin
IWE Wound Filters 20" x 2.5"
IWE Wound Filters 30" x 2.5"
Jumbo Filters 10" x 8"
Jumbo Filters 20" x 8"
Jumbo Filters 31" x 8"
Juraperle
Knife Gate Valves
Legris LF3000 Fittings
Level Controls Optional Extras
Light Commercial UV Water Filters
Loft Coffin Tanks
Loft Tanks
Magnesium & Calcium
Magnodol
Manganese
Manganese Dioxide
Marine Calcium
Melt Blown Cartridge Filters 2
Melt Blown Filters 10" x 2.5"
Melt Blown Filters 10" X 4"
Melt Blown Filters 20" x 2.5"
Melt Blown Filters 20" x 4"
Men
- T-Shirts
Metal Push In Fittings
Mini Ball Valves
Mixed Bed Controllers – EC3020
Molasses Tanks
Multijet Beta SDC
Music
- Albums
- Singles
Nickel
Nitrate Reduction Resin
Nitrate Removal
Nitrite
NMB Pure Water Deionisation
NMB Pure Water Deionisation Exchange
NW 500 650 800 Bag Filters
NW Range Spares
Nylon Hosetails
Nylon Polyurethane PTFE Tubing
Oil Reduction Filters 10" x 2.5"
Oil Removal Cartridge Filters
Oil Removal Filters - Multi Cartridge Type
Oil Removal Filters - Single Cartridge Type
One Flow Anti Scale Cartridge
One Flow High Flow Cartridge
One Flow Hot Water
One Flow Industrial
One Flow Industrial High Flow
One Flow Residential
OneFlow Anti-Scale Systems
Open Top Cone Storage Tanks
Open Top Tanks
pH Conductivity and Redox Solutions
pH Testers
Phosphate
Phosphorus
Pipe Fittings
Plasshield for Barrier Pipe
PlassOne Push to fit fittings
Plastic Bag Filter Housings
Plastic Bag Filter Housings - 20 Inch
Plastic Cryptosporidium Filters
Plastic Push In Fittings
Plastic Water Tanks up to 1000 Ltr
Pleated Cartridge Filters
Pleated Cartridge Filters
Pleated Filters 10" x 2.5"
Pleated Filters 10" x 4"
Pleated Filters 20" x 2.5"
Pleated Filters 20" x 4"
Polypropylene Float Valve
Posters
Potable Storage Tanks
Pressure Boosting Pumps
Pressure Gauge - Back Entry 0 to 100 psi
Pressure Gauge - Back Entry 0 to 200 psi
Pressure Gauge - Side Entry 0 to 200 psi
Pressure Reducing Valve - Union Ends
Pressure Reducing Valve – Screwed BSPP
Pressure Reducing Valve with Gauge
Pressure Vessel Accessories
Pressure Vessels
Pressure Vessels
Pressure Vessels - 2 1/2" Top Hole
Pressure Vessels - 4" Threaded Top Hole
Pressure Vessels – 4″ Threaded Top & Bottom Hole
Pressure Vessels – 6" Flanged Top & Bottom Hole
Pressure Vessels – 6" Flanged Top Hole
Pumps Training Course
Push in Olab Fittings
Quick Fittings
Rack Range
Rainwater Harvesting - Commercial Filters
Rainwater Harvesting - Pre Tank Filter
Rainwater Harvesting Filters
Rainwater Harvesting Kits
Rainwater Storage Tanks
Range 81 Double Bag Filters
Range 81 Replacement Filters
Range 84 Bag Filters Double
Range 84 Bag Filters Single
Range 84 Bag Filters Triple
Range 84 Filter Housing
Range 88 Stainless Steel Housing
Ranger 45 Slide Incubator
Recoils
Rectangular Tanks
Reinforced PVC Tube
Resin Qualitative Test Kit
Reuseable Fittings
Reverse Osmosis - Compact IBC Range
Reverse Osmosis - Compact Range
Reverse Osmosis - Pro Max 4 Range
Reverse Osmosis - Pro Range
Reverse Osmosis Controller OS3015
Reverse Osmosis Controller OS3020
Reverse Osmosis Controller OS3030
Reverse Osmosis Controller OS3050/51
Reverse Osmosis Controller RGS8000
Reverse Osmosis Pro Max 8 Range
Reverse Osmosis Water Filters - upto 150 lph
RO Membrane Housing ABS End Caps
RO Membranes 10 Inch x 2 Inch
RO Membranes 10 Inch x 3 Inch
RO Spares
Rubber Hose
S-Line UV Water Filters
Sapphire Domestic Water Softener
SCE Range For Water Hardness
SCE Range For Water Hardness Exchange
SDB Range UV Spares
SDE Range UV Spares
SE Range
Seawater Range
Shoes
Siata 300 Pro Filter
Siata Duplex 132
Siata Duplex 250
Siata Duplex 360
Siata Simplex 132 Meter Controlled
Siata Simplex 132 Time Clock
Siata Simplex 230 Meter Controlled
Siata Simplex 230 Time Clock
Siata Simplex 250 Meter Controlled
Siata Simplex 250 Time Clock
Siata Simplex 360 Meter Controlled
Siata Simplex 360 Time Clock
Siata Simplex Activated Carbon
Siata Simplex Birm
Siata Simplex Filox R
Siata Simplex Multimedia
Siata Simplex pH Correction
Siata V132 Service Kit
Siata V230 Service Kit
Siata V240FE Service Kit
Siata V250 Service Kit
Siata V260 Service Kit
Siata V360 Service Kit
Siata Valves Training Course
Silencers
Silica Low and High Range
Silverline CS110 Spares
Silverline CS165 Spares
Silverline CS220 Spares
Silverline CS330 Spares
Silverline CS440 Spares
Silverline CS550 Spares
Simplex CAT 5 Booster Variable
Simplex CAT 5 Break Tank & Booster Pump
Sita AM Spares
Sita Domestic UV107 Spares
Sita DS Spares
Sita Rack Spares
Sita Range
Sita SE Spares
Sita UV AM Range Spares
Sita UV DS Range Spares
Sita UV SE1 Range Spares
Sita UV SE2 Range Spares
Sita UV SE3 Range Spares
Sita UV SE4 Range Spares
SMP Range
Spring Check - Wafer type NBR
Spring Check - Wafer type PTFE
Spring Check - Wafer type Viton
SPS Range UV Spares
SS 15 Range Spares
SS Range
SS1475 Range Spares
SS1475 UV Spares
SS15 UV Spares
SS1575 Range Spares
SS1575 UV Spares
SS30 Range Spares
SS30 UV Spares
SS55 Range Spares
SS55 UV Spares
SS75 Range Spares
SS75 UV Spares
Stainless Steel Ball Valves
Stainless Steel Butterfly Valves
Stainless Steel Cartridge Filter - 62 Series
Stainless Steel Cartridge Filter 61 Series
Stainless Steel Cartridge Filters
Stainless Steel Float Valve - Flanged
Stainless Steel Float Valve - Threaded
Stainless Steel Needle Valves
Stainless Steel Pressure Reducing Valves
Stainless Steel Solenoid Valves
Stainless Steel Y Strainer Flanged
Stainless Steel Y Strainers
Standard GRP Pressure Vessels
Static Storage Tanks
Storage Tanks Under 1000 Ltr
Strainers
Sump Tanks
Sweaters
Swing Check – Wafer type EPDM
Swing Check – Wafer type NBR
Swing Check – Wafer type PTFE
Swing Check – Wafer type Viton
Testomat 808
Testomat 808 Reagent
Testomat Eco
Testomat Eco Indicator Liquids
Testomat Service Kits
Thermometers
Titration Equipment
Toray 4" Membranes - Hot Sanitisable
Toray 4" Membranes - NF
Toray 4" Membranes - SU BWRO Low Pressure
Toray 4" Membranes - SU BWRO Standard
Toray 4" Membranes - SU BWRO Ultralow Pressure
Toray 4" Membranes - SWRO
Toray 8" Membranes - BWRO Low Fouling
Toray 8" Membranes - BWRO Low Pressure
Toray 8" Membranes - BWRO Ultralow Pressure
Toray 8" Membranes - Hot Sanitisable
Toray 8" Membranes - NF
Toray 8" Membranes - SU BWRO Low Pressure
Toray 8" Membranes - SU BWRO Standard
Toray 8" Membranes - SU BWRO Ultralow Pressure
Toray 8" Membranes - SU SWRO
Toray 8" Membranes - SWRO
Toray 8" Membranes BWRO Standard
Tulsion Ion Exchange Resin
Turbidex
Turbidity Meters
Ultrafiltration Controller – UF2050
Ultrafiltration Controller – UF3020
Uncategorized
Underground Tanks
UPVC Class E Pipe
uv filter atlas average family
uv filter atlas light commercial
uv filter atlas small house
UV Filter Average Home ST08
UV Filter Light Commercial ST08
uv filter small cottage atlas
UV Filter Small Cottage SDE
UV Filter Small Cottage SPS
UV Filter Small Cottage ST08
UV Filter Small House SDE
UV Filter Small House SPS
UV Water Filter Kits
Valves and Gauges
Vertical Storage Tank
VHP Ultra Pure Water
VHP Ultra Pure Water Exchange
VMB Exchange For High Quality Water
VMB For High Quality Water
water cartridge filter housings 2.5 x 10
water cartridge filter housings 4 x 10
water cartridge filter housings 4 x 20
Water Composition Training Course
Water Filter Controller - ES2030
Water Filter Controller - ES2030SV
Water Filter Controller - ES2050/51
Water Filter Controller - ES2070TV
Water Filter Media
Water Filters
Water Filters Training Course
Water Hardness Test Kits
Water Safety Device
Water Softener Salt
Water Softeners
Water Softening & Iron Cartridge Filter
Water Softening Iron Reduction 10" x 2.5"
Water Storage Tank
Water Storage Tanks
- Slimline Tanks
Water Storage Tanks - 100 to 199 Ltr
Water Storage Tanks - to 1000ltr
Water Storage Tanks 1000 to 1199 Ltr
Water Storage Tanks 10000 to 11999 Ltr
Water Storage Tanks 1200 to 1499 Ltr
Water Storage Tanks 12000 to 14999 Ltr
Water Storage Tanks 1500 to 1999 Ltr
Water Storage Tanks 15000 to 16999 Ltr
Water Storage Tanks 200 to 299 Ltr
Water Storage Tanks 2000 to 2999 Ltr
Water Storage Tanks 20000 to 24999 Ltr
Water Storage Tanks 25000 +
Water Storage Tanks 300 to 399 Ltr
Water Storage Tanks 3000 to 3999 Ltr
Water Storage Tanks 400 to 499 Ltr
Water Storage Tanks 4000 to 5499 Ltr
Water Storage Tanks 5 to 59 Ltr
Water Storage Tanks 500 to 599 Ltr
Water Storage Tanks 60 to 99 Ltr
Water Storage Tanks 600 to 699 Ltr
Water Storage Tanks 6000 to 6999 Ltr
Water Storage Tanks 700 to 799 Ltr
Water Storage Tanks 7000 to 7999 Ltr
Water Storage Tanks 800 to 999 Ltr
Water Storage Tanks 8000 to 8999 Ltr
Water Tanks
Water Test Strips
Water Treatment Training Course
Woltmann Omega
Women
- Jeans
- Tops
Wound Cartridge Filters
Wound Cartridge Filters 10" x 4"
Wound Filters 10" x 2.5"
Wound Filters 20" x 2.5"
Wound Filters 20" x 4"

Description

Chlorine Dioxide VLR

About us

As one of the UK's and Irelands largest and most experienced water equipment suppliers. We are able to offer a complete range of water treatment services and stock a massive range of equipment and spares, most available to buy online.

Ravenstor Road
Wirksworth, Matlock, Derbyshire
DE4 4FY

Trade Customers

To apply for a trade account please complete our account application form.

Contact

Telephone 01629 363311

Option 1 – Sales
Option 2 – Tech Support
Option 3 – Service
Option 4 – Accounts
Option 5 – Operator
Option 6 – 24/7 Emergency Breakdown

info@industrialwaterequipment.co.uk

Stripe

Apple Pay

PayPal

Bank Transfer

BLOG
LATEST NEWS
CONTACT US
FAQ

TERMS & CONDITIONS | RETURNED GOODS POLICY | PURCHASING TERMS | PRIVACY POLICY |

Copyright 2025 © Industrial Water Equipment Ltd

Search for:
Water Treatment
Spares & Parts
Media & Consumables
Services
Login / Register
Newsletter
CONTACT