Amazon.com : Premium USA Made Pop-Up Drainage Emitter, for 3 in. & 4 in. Drain Fittings, Green Plastic - for Outdoor Landscape Sewer & Drain Pipe (Pop Up Valve Only) : Tools
Pop-up Sewer Relief Valve for 3" or 4" PVC Pipe | GETPVF
Tempo pop-up valve drainage emitter w/ 3" elbow
NDS Pop-Up Drainage Emitter with Elbow for 3 in. Drain Pipes, Green Plastic 322G - The Home Depot
Clemco Pop-Up Valve Seat, Neoprene 4 inch I.D. x 5 inch O.D.