SP Air Corporation SP-1850S Baby Butterfly 1/4-Inch Palm Impact Wrench Small and lightweight palm-size design but very powerful Double-hammer mechanism produces more power with balanced impact blows Built in air regulator and 160 degree swivel air inlet Butterfly throttle for one hand forward and reverse operation Durable and high quality construction expertly made In Japan Small and lightweight palm-size design but very powerful Double-hammer mechanism produces more power with balanced impact blows Built in air regulator 160 degree swivel air inlet Butterfly throttle for one hand forward and reverse operation