3/4" x 3/4"d, sharkbite evopex push only to connect coupling, designed to use without the need for additional tools & rings, no special tools, soldering, glue or crimping to plumb an entire home, reduces the risk of install errors & potential leaks, just push onto pex pipe & check the green visual indicator to ensure a proper, leak free connection, made from acudel plastic, provides toughness & chemical resistance along with excellent anti-decay stability & dimensional stability.