This Ultimateaddons handlebar mounting attachment can be used with any of UltimateAddons 3 prong device holders and cases. This quick release attachment allows you to quickly and easily remove your holder/case form your vehicle while leaving the attachment connected. The UltimateAddons quick release attachment can be fitted to vehicles handlebars / frame with a diameter between approx. 21mm - 30mm. The mounting attachment has a rubber grip inside to help with securing it. There is an easy-twist screw to tighten the attachment to the required size. The mounting attachment consists of a 3 prong patented system which allows an UltimateAddons holder / case to be fitted to it, designed in a way where it is easy to click and lock the holder / waterproof case into place. The quick release plate is now fitted with a secure locking system.