The AP142017MM adapter converts your 1/4"-20 compatible tripod or monopod into a 17mm smartphone mount. This adapter fits all tripods and monopods utilizing the 1/4"-20 screw pattern, and is compatible with Arkon's MG002WR Mobile Grip 2 Universal Smartphone Holder. (Holders and devices sold separately.) Screw the adapter onto the tripod, attach the 17mm ball Mobile Grip 2 Holder onto the 17mm ball, then mount your smartphone. This adapter allows your tripod or monopod to function as a selfie stick for your smartphone. Hold up the smartphone tripod to get a better shot of the action at concerts, parades, and other public events.