The SAFE-T-STOPPER works on many different types of tees. Cap Tee CAP TEE CAP TEE ON SADDLE DRESSER QWIK TAP TEE CAP TEE ON COUPLING Mueller Tee MUELLER TEE MISSING COMPLETION PLUG Punch Tee Saddle TEE WITH BARREL CAP STREET TEE ON SADDLE Plug Tee STREET TEE ON SADDLE PLUG TEE ON WELDED NIPPLE Elbow Service STREET ELBOW ON COUPLING F X F ELBOW SERVICES SKINNER TEE CAP TEE WITH RUBBER FLAP VALVE PLUG TEE WITH BUSHING FLAP SKINNER TEE FLAP VALVE PE Bolt-On Tee