this waterproofing pipe seal is made of quality polyethylene waterproofing membrane, and the middle gasket is made of quality rubber, effectively waterproof, which can prevent pipe from leaking or being corroded by water. The waterproofing pipe seal can be easy to achieve a watertight installation where you need to install, and can be fixed in place with thin mortar, which can fit the shower pipe or bathtub outlet well. 

3/4" (20 mm)