Jackel Sump Check Valve (Model: DJ-545)

Amazon.com Price: $11.98 (as of 26/09/2023 11:33 PST- Details)

Fits 1-1/4″ or 1-1/2″ black, galvanized or DWV Schedule 40 pipe
The most durable flapper in the industry
Strong and durable ABS body