The HFS30 series are an extreme pressure quick connect (10,000 psi) that are commonly found on hydraulic jacks, rams, power packs, and other ultra-high pressure equipment. They are interchangeable with similar couplings in the same size, regardless of the valve style (they are considered an Industrial Hydraulic Interchange so they will not interchange with some Automotive styles). Poppet valving improves sealing, increases burst pressure, and provides less flow restriction (ball or poppet type checks are interchangeable, however ball & poppet type are not designed for use with each other and may affect performance). Compatible with New-Line NS30 series, Aeroquip WA5600 series, Parker 3000 series, Enerpac C604, Faster PVV, Dayco QD3 series, Perfecting T series, and many others.