The ATP B3Z-HD Counter-Clockwise, Rope Seal type Pump is a 4″ x 3″ Centrifugal Frame Mounted Water Pump. This Heavy-Duty pump has a 11⁄2″ Shaft with 3⁄8″ Keyway, and a KEYED Impeller with 11⁄4″ Bore, making it stronger than the standard B3Z. This pump is THREADED on both the suction and discharge side and at 2500 RPM, performs at a rate up to 800 GPM at 70 PSI. When driven directly via PTO, this pump is used for trucks with Standard Transmissions. This ATP Water Pump is a direct replacement for Berkeley Pump B3ZRM (B85874). Check out our Water Pump Guide for more information on pump rotation, connections and seal type.