K & L Supply Company 90-Degree Valve Stem At last, you can easily check and inflate your tires, regardless of brake or driveline configurations. Features: Right angle valve stem is a direct 90 deg. bend form the surface of the wheel rim 8mm diameter rim opening required Aluminum construction Makes it easy to inflate tires on dual disc wheels The short stem is ideal for use on rear wheels Made of lightweight aluminum, so they won't affect your wheel balancing