concealed door closer material: aluminium color: silver, brown, black, and others door weight 65-90kg 1, Item name: Door closer2, Item number: VW ... data picture: 20,Installation sketch map of exoteric door closer: 21,Latching speed adjustment and Closing speed adjustment: 22 ... in 3 seconds from 90°, slowly door closing above 40 seconds. Buffer function: door closer will create resistance to avoid too ...