AK124 3/4" Bore OD 12.25", 1 Groove V-Belt Pulley Gear AK124-3/4" Cast Iron for 3L , 4L for V-belt size A Outside diameter: 12" , 12.5 inch Length through bore: 1.1563" inch Bore: 3/4" inch Belt section size: 3L, 4L , Material : Cast Iron One pulley 2 Hex set screw Keyway