... cover 2,120,000 times open and close and not oil leak 3,use for machinery&bed & boor 1,Fully gas spring for ... the gas spring can be very closely controlled in either compression or extension .3,A release valve ... requied .4,We are looking forward cooperating with you and your company.if you want , ... 50012*26200-150080500-1300200-60014*28200-2000100Features: 1, Gas: Nitrogen filled inside. 2, Color : black, ...