These trailer pumps have been redesigned for better maneuverability and towing while adding Cat power for a wider range of service options. The new 750-15 has an 18-in. shorter frame and is 600-lbs lighter , without sacrificing durability. The all-hydraulic pump-kit and Rock Valve remain the same, providing up to 50 cu yds/hour output and 1100 psi on the concrete while pumping concrete with up to 1.5-in. aggregate. Schwing.