Jagwire cable ferrule 4mm plasticjagwires sealed end caps feature a small rubber o ring in the base to help prevent dirt and moisture from entering the housing made from a durable plastic these sealed end caps can be fitted to the end of 4mm gear housing to protect your inner cables and ensure you enjoy crisp smooth shifting for longer features sealed end caps feature a small rubber o ring in the base to help prevent dirt and moisture from entering the housing for use with shift systems ma