Plumbing codes require that hand-held showers be provided with backflow protection.
Backflow protection can be an air gap, two independent check valves, or a vacuum breaker.
All KOHLER® handshowers contain an integral check valve, which also functions as a flow control.
If a second check valve is required, a handshower hose that contains a check valve should be used.
If additional backflow prevention is required, installation of the K-9660 vacuum breaker is recommended.
Refer to the product specification sheet for the presence of check valves for backflow protection.