You can adjust the speed to open the door, and it has traditional type, slim type and concealed type

Model # 982:  Overtake weight for door: 30kgs 

Model # 983:  Overtake weight for door: 65kgs 

Model # 984:  Overtake weight for door: 85kgs 

Model # 985:  Overtake weight for door: 120kgs 

2) Material: aluminium

3) Function: adjust the speed to open the door