Universal Tool Air Hammers feature precision engineered spool valves for precision control on the job and triple heat treated alloy steel cylinders and pistons. Universal Tool Air Hammers also feature powder coated acrylic coating for insulation. Universal Tool Aero Riveting Hammers are best suited for closing rivets in air frame assembly.Universal Tool Bench Rammers feature a high power to weight ratio and a heat treated cylinder and piston for durability. Universal Tool Bench Rammers also feature a threaded retainer for quick and easy butt changes, and are easily operated and guided. Universal Tool Bench Rammers are best suited for compacting sand, soil and other fiber materials.