Holder replacement packs of 2, 3 or 5 allow the active GoPro Hero3 user to use and abuse their GoPro holder without the need to repurchase a full kit. The holder system fits snugly over the housing and fastens securely with a single thumb screw. Because the holder is designed to hold 2 filters it is easy to stack them for different effects, or to add a clear filter as an extra layer of protection. The holder system is designed to attach to the housing of the GoPro camera and two size options are available; Hero 3 (wrist and dive housing) and Hero 3+/4.