The "Rolls Royce" of marine oscillators, the York is a twin 3/8 inch engine, double-acting with regulator/reversing lever, displacement lubricator and boiler feed pump. This factory-built engine has had very little use and comes complete with original instructions. Operates from 10 to 80 psi, minimum 20 psi if pump is used. In as-new condition. 5 inches wide x 3 1/2 high.