Body aluminum alloy, internal parts steel; flow control device spring loaded poppet; media for which designed hydraulic oils; recommended for relief pressures to 5000 psi /350 bar/; thds 0.500 in. Bsppl; screw adjust means; 25psi adjustable range; 7.56 in. Lg; seals included; 1.250 in. Thick; 2.000 in. Wide; 40 gpm