This Gray Schedule 40 PVC 1" Slip x 1" MPT x 1" FPT Swivel Manifold System Tee has nitril rubber O-rings in all female threaded connections, so no pipe dope or teflon tape is needed. Assemble valves without gluing for an easy to repair/replace valve manifold system. Hand tighten threaded connections only. Slip connection does require solvent welding.