Andoer Aluminum Thumb Knob Stainless Bolt Nut Screw Set for GoPro HD Hero 1 2 / 3 / 3+ ST-50 (Purple) Aluminum thumb knob with stainless bolt nut screw for Gopro mount adapter. Made of high quality aluminum, durable for long term use. Easy to install and use. Accessories for fixing Gopro to a standard tripod, suction cup.