I ordered a Secure Ring Door Security Chain for our front door from Doorfit on 10th October,2018. The unit was delivered to my home the following day. It was a quality piece of hardware but unfortunately was not compatible to the door handle on the front door in that the ring would not slide over the door handle due to the thickness of the handle. This only became apparent upon offering the unit to our front door. I immediately contacted Doorfit who agreed I should return the unit for a refund, which I did. I should point out our front door and ironmongery is at least thirty years old. I am sure the Secure Ring Door Security Chain is compatible with more modern door ironmongery. I found Doorfit most helpful and understanding.