The main column for this hammer is plumbed as an air chamber, this greatly increases the efficiency of the compressor. All of the air fittings, valves and cylinder are of the highest quality and made in the USA. A gantry style caster system, designed by Jason, allows 1 person to roll this hammer around and then after turning 4 bolts lower it to the floor. Dual shield welded. Weight 1800 lbs. Plans by Ron Kinyon.