Check-Flex G5-S0100
Ø 106-113mm L: 190mm
Check-Flex G5-S0100+G
Ø 114-125mm
Check-Flex G5-RESI-S0125
Ø 126-149mm
Check-Flex G5-S Build to Order
Check-Flex G5-S Inline Valve
Inline Rubber Check Valve with adjustable seal to pipe
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Vulcanised and reinforced like a tyre for durability
Flexible and wide seal
Flange drilling to match any mating flange
Sizes to fit all pipes
Encapsulated metal with strong single piece design for marine diffuser applications
Nominal Pipe Size


Installing a 900mm into a twinwall pipe in a curved-face seawall. Check-Flex G5-S valves have an adjustable clamp set that expands and seals to the pipe wall. The valve is inserted until fully enclosed and then the clamps expanded to create a water seal. Simple to install in a tidal window. The valves can withstand waves without protection.
I saw the new Check Flex Valves this week, they certainly exude quality in build and construction
- Mike - Project Manager, Trunk Sewers and Strategic Pumping, UK
Thank you again for your valuable support—it really makes a difference for the project
- Maria, Design Engineer Denmark
The pipe ID varies between chambers and the stainless steel valve does not fit, the expanding clamp sealed easily to these pipes
- Charlie - Technial Services Engineer, Airport UK

The Check-Flex G5-S inline valve can be installed into angled pipes. The adjustable clamps expand and compress the gasket end to seal to the pipe.

Check-Flex G5-S inline valves fit inside benching. The valve is a little smaller than the pipe ID. Usually fitted to the outlet of a chamber for ease of inspection. Ideal for commercial site installation within property boundary.

Check-Flex G5-S inline valves will seal to lined pipes. Valves are available in any pipe size to ensure optimal performance.
| Model | Style | Pipe Size Range | Pipe Connection | ||||
|---|---|---|---|---|---|---|---|
| -S | -C | -W | -F / -Fi / -Fd | -G | |||
| G5 | Inline Fabricated | 80–3000mm | - | - | - | - | |
| G5M | Inline Moulded | 100–150mm | - | ||||
| G5-RESI | Inline EN13564-1 | 80–200mm | - | ||||
| G4 | Duckbill Fabricated | 100–2400mm | - | - | - | - | - |
| G3 | Duckbill Fabricated | 100–2400mm | - | - | - | - | - |
| G3M | Duckbill Moulded | 100–150mm | - | ||||
| G2 | Inline Duckbill Fabricated | 50–300mm | - | ||||
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