Prime-Line H 3715 Tee Handle Crank with 3/8-Inch Bore, White, (Pack of 2) Features a 3/8-inch inside diameter; for use with 3/8-inch outside diameter splines Mounts secure over 3/8-inch splines with tightening of set screw White painted finish Diecast construction Used with crank out casement operators manufactured with 3/8-inch splines