THE TWIN HAMMER MECHANISM HAS TWO IDENTICAL HAMMERS DELIVERING SIMULTANEOUS BALANCED IMPACTS. THIS DESIGN IS AN IMPROVEMENT OVER OTHER MECHANISMS REDUCING VIBRATION AND DELIVERING GREATER TORQUE. 6"" EXTENDED ANVIL TO REACH DEEP AREAS. REVERSE VALVE EASILY CHANGES DIRECTION. CHOKE VALVE AND CONTROLLED START ALLOW THE USER TO EASILY LOOSEN THE PIN.