Products OS-021 OS-021 Red Copper PlatedInside diammeter: 18mm View more OS-002 OS-002 Zinc Brass PlatedInside diammeter: 18mm View more OS-010-1 OS-010-1 Zinc Brass PlatedInside diammeter: 18mm View more OS-009 OS-009 Zinc Brass PlatedInside diammeter: 18mm View more OS-009s OS-009s Zinc Brass PlatedInside diammeter: 13mm View more