The T3 Transfer Pump combines Graco’s proven Merkur air-motor and popular T2 lower. The Merkur air-motor is based on air pilot valve technology. The air-motor switching is purely pneumatic. This differs from T1 and T2 Transfer Pumps, which use a mechanical reversing mechanism in the air-motor. The T3 is a 3:1 ratio pump – using less air pressure to provide the same fluid pressure required.