Certain KOAH models are constructed with a closed muzzle for added strength. This greatly adds usage life and strength to the speargun, however it can make band replacement tricky. To solve this problem we came up with the closed muzzle band. Constructed from the same material as the original power bands, just modified with a simple loop and tie apparatus. Just order the size you are looking for and it can be tied into your KOAH Euro or closed muzzle KOAH Bluewater. Installs in seconds.