SIL 3, ATEX, CE. Waterproof protection: O-rings are fitted between body and cover and other connection position, this ensures waterproof protection. Corrosion resistant: sprayed with a multilayer protective coating to meet the environmental requirements of all kinds of working conditions. Spring return models in excess of 3,000,000 lbs-in, double-acting 12,581 – 6,000,000 lbs-in. Pneumatic operating pressure: 40 psi – 90 psi. Ambient temperature: -40F to 300F.