If you already have a 25mm 1" ball attachment connected to your motorcycle you can use this 25mm to 3 prong adapter to connect to Ultimateaddons cases / holders. Please note that this is compatible with a range of manufacturers but is designed to work with Ultimateaddons. This is now supplied with new locking mechanism on the 3 prong attachment. Please note images are for illustration purposes only and listing is for adapter only.