This universal mount is capable of holding multiple devices simultaneously. Compatible with 31.8mm handlebars and comes with hardware and an adapter for mounting the Koala Bottle system. Weight with the Koala Bottle adapter is 123g. For adapters to mount other devices such as CatEye, GoPro, Garmin, or NiteRider lights please visit www.womodesigns.com. The Koala Bottle system is sold separately.