GZ43523 – GROZ 17.0MM HD-SERIES HYDRAULIC COUPLER 3-JAW Max. Pressure – 10000PSI / 690BAR. Thread – 1/8IN BSPT. 3-Jaw with Ball Check. For use with hand & air operated Grease Guns. Recommended for use with air grease guns. Hardened coupler body withstands high pressure without deformation. Fully hardened spring steel jaws. Hexagonal nut for easy tightening.