BuyBits 1" (25mm) Socket to 17mm Ball Adapter for Garmin Nuvi Holders fits RAM Mounts Unique mount adapter which allows you to attach most Garmin Nuvi cradles/holders to 1 inch (25mm) ball mount bases. Use with RAM motorcycle mounts, Ultimate Addons, BuyBits & SW-Motech. Compact design - height approx 7cm. 17mm ball fits most Nuvi cradles - simply push into the (female) recess. Designed for secure dedicated cradles / holders - holder NOT included