1. Passed SGS for over 50,000 open-close test 2. Finish: spray painting 3. Eliminate noise to design 1. Material: Seamless steel pipe Q235, Brass H62, Hydraulic oil, cold-rolled steel, silicon, plastic, Zinc alloy ZnAI42. Function: up opening the door,holds the door in any position after opening angel is more than 35°, convinent for touching control, soft closing.3. Application: all upward ...