product manual:

3-way to adjust the arm ---- allow 3-way rotation adjustment, to ensure you can get your ideal shooting angle. Can be used with Roll Bar Mount large diameter bracket, Handlebar Seatpost Mount small diameter bracket, Cheast Mount Harness chest strap, Head Strap headband, Vented Helmet Strap ventilated helmet belt, with a variety of accessories, powerful, wide range of use, absolutely Your essential accessory.

Compatible with all original Gopro Hero3, Hero2, HD Hero cameras.