1,this lockable gas spring is our best seller 2,When it lock,it will rigid. 3, ... looking forward to cooperate with you, we will provide best service to you.if you want ,pls let us ... provide fatigue test report. Our products can open and close 100,000 times, Not leak oil; Our paint is passed ROHS test; ... 4,When the gas spring is up and down, it's ...