HEYCO 2509 ( HEYCO DD-875-770 ) HOLE PLUG, NON-METALIC, BLACK, 1-1/64 INCH OUTSIDE PLUG DIAMETER, FOR 7/8 INCH DIAMETER HOLE. HEYCO PRODUCTS, INC. DESCRIPTION DD-875-770, PART NO. 2509 (BLACK) (SHIPPING QTY. 100 EA.)