The Ermes Formula inverted roller speargun muzzle with ceramic bearings is small, lightweight, and made entirely of nylon with 30% fiberglass. In the center of the muzzle, there are attachments for the inverter system. The 30 mm pulleys are protected by a fairing and can accommodate high-speed ceramic bearings. Additionally, there are two O-ring seats that make it suitable for mounting a 26 or 26.5 mm barrel.