The most common elastomer used is Chloroprene CR, commonly called Neoprene. Other available elastomers include Buna-N, EPDM and Nitrile; to meet a known site risk, usually industrial or storage sites.
The exposed metal clamps are stainless steel 316L EN 1,4404.
The typical levels of H2S, and contaminated highway runoff, saltwater, and cleaning chemicals to not affect the valves.

Flanged connections conform to pipe standards and are ideal when there is a mating pipe flange. Diffuser valves G3 are often specified with flanges so that divers can fit valves underwater with limited visibility. Flange connections -F have the same pressure rating as -S valves.

G5-S valves are typically fitted to the outlet pipe from the last chamber. This prevents the chamber from flooding. Visual inspection of the valve performance can often be done without entering the chamber.

We stock the G5-S and G5M-S models in all sizes from 50-1200mm. The G4 duckbill valves are stocked to 100-900mm

Large valves, over 1200mm are built to order to suit a particular pipe and application. Smaller valves for diffuser applications that are conforming to an exit velocity are BTO

We have STEP files, to ISO 10303 available. These can be imported into any CAD software.

Check-Flex valves are tested independenly at Utah State Water Research Laboratory UWRL, at the factory to meet specific site requirements and we test valves up to 300mm.

Both duckbill and inline valves perform well when fully submerged, preventing backflow effectively. In partially submerged conditions, however, the inline valve is at a disadvantage: its higher cracking pressure and slower response time work against it.

The key factor is submerged surface area. A duckbill valve presents roughly 4 times more effective area underwater than an inline valve, which translates directly into more force available to open it. This gap widens further when the inline valve's circular face isn't fully submerged, since only the wetted portion contributes to opening force.

As a result, a duckbill valve typically responds within a single wave period, while an inline valve lags behind.

The valves have some clearance and the settlement will be angular, at the joint, rather than a shearing movement. As the G5 valves are short, they are not often across a rocker pipe joint. We have installed in rocker pipes without issue.Specific site design sizes can be confirmed.