Designed to seal monitor wells. Sized to seal Schedule 40 piping. 2" and 4" sizes can also seal schedule 5 plastic and stainless steel pipe. Yellow chromate-coated locking latch accepts Cherne's solid brass padlock or No. 2 Master padlock. 0=Meets all EPA requirements for locking plugs. Made with chemical-/petroleum-resistant Estaloc plastic top/bottom plates and Nitrile sealing O-ring. Comes with stainless steel carriage bolt.