Feature: 1. Gas: Nitrogen(99.999%). 2.Long life :150,000 cycle life time,one cycle means one up and one down . 3. Material: finishing rolling seamless steel tube for cylinder, steel for piston rod. 4. Surface: spray painting for cylinder, QPQ for piston rod. 5. Color : black, or as your requirement. 6. Operating Temperature Range: -15~+80℃(5~176℉)as standard; -50~+80℃(-58~+176℉) or -15~200℃(5~392℉) are available.