REED-PRENTICE "TIMBERHOG" Air saw. AIR-SAW (pneumatic) REED-PRENTICE Description:The front helper has a knob at the end of the handle to add tension to the chain.The lever on the left of the "helper handle" is a hand pump that you unscrew and pumping action is used to built pressure inside the oil tank.The on/off rotating button is selected for "cutting" or "felling"...one button on each side to allow different oil passages lubrication to the chain.The unit can be opened on the side using a "slider/wing nut" and thus allowing to open a trap door mounted on a swivel.The quantity of chain oil is controlled by a screw valve on the side.The head has a variable air control and a lock on full load position.Operation requires 75PSI to 95PSI at constant 70CFM(Cubic feet per minutes).