Mill Oil Is a lubricating oil used in the processing of steel. Various formulations are utilized depending on the process such as hot rolling, cold rolling and tubular rolling of steel. 4195 Cast iron Pressures up to 250 PSI Capacities to 580 GPM 4124A Cast iron Ambient temperature Mechanical seal options Capacities to 500 GPM 1124A Cast iron Abrasive resistant sealing option Hardened iron bushings and hardened steel shaft Capacities to 400 GPM