Fits ST-18 tubes 1.84"

Semroc Centering Rings Plywood LT-115(BTH-52) to ST-18(2pk) SEM-CR-115-18P

Semroc Centering Rings Plywood LT-115(BTH-52) to ST-18(2pk) SEM-CR-115-18P Laser-Cut Tough Fiber Rin…

Semroc Centering Rings Fiber BT-50 to ST-18 (2 ring set with engine hook slot) SEM-CR-50-18EH

Semroc Centering Rings Fiber BT-50 to ST-18 (2 ring set with engine hook slot)   SEM-CR-50-18EH Lase…

Semroc Centering Rings Plywood ST-9 to ST-18(2pk) SEM-CR-9-18P

Semroc Centering Rings Plywood ST-9 to ST-18(2pk)  SEM-CR-9-18P Laser-cut plywood rings which center…

Semroc Centering Rings Fiber ST-7 to ST-18(2 piece set with engine hook slot) SEM-CR-718EH

Semroc Centering Rings Fiber ST-7 to ST-18(2 piece set with engine hook slot)   SEM-CR-718EH Laser-c…

Semroc Plywood Block or Bulkhead for ST-18 tube(2 ring set) SEM-PB-18

Semroc Plywood Bulkhead Block for ST-18 tube(2 ring set) SEM-PB-18 Used as lightweight bulkheads for…

Semroc Centering Rings Fiber ST-11 to ST-18(2pk) SEM-CR-11-18

Semroc Centering Rings Fiber ST-11 to ST-18(2pk) SEM-CR-11-18 Featherweight laser-cut fiber rings w…

Semroc Centering Rings Fiber ST-9 to ST-18(2pk) SEM-CR-9-18

Semroc Centering Rings Fiber ST-9 to ST-18(2pk)   SEM-CR-9-18 Laser-cut rings for centering a ST-9 t…

Semroc Centering Rings Fiber ST-7 to ST-18(2pk)(same as CR-KA-11) SEM-CR-718

Semroc Centering Rings Fiber ST-7 to ST-18(2pk)   SEM-CR-718 Laser-cut rings for centering a ST-7 mo…

Semroc Centering Rings Fiber BT-50 to ST-18(2pk) SEM-CR-50-18

Semroc Centering Rings Fiber BT-50 to ST-18(2pk)   SEM-CR-50-18 Laser rings for centering a BT-50 mo…

Semroc Centering Rings Fiber ST-10 to ST-18(2pk) SEM-CR-10-18

Semroc Centering Rings Fiber ST-10 to ST-18(2pk) SEM-CR-10-18 Laser-cut rings for centering a ST-10 …