1.Simple installment ,the soft closing damper only use one crew and one buckle, no need to use othet measure tools                      2.Special V form with spread structure is anti-jump prevented, suitable for doors with different weight                                              3.The upper fixer can adjust up and down by one key to match upper wheel height requirment                                                        4.Self-regulation design of upper wheel can make sure the best height of the door, simple installment.                                            5.Suitable for off-centre mullion                                                                                                                                                  6.Fit for 38mm-40mm up track