Semroc Centering Rings Fiber ST-7 to ST-18(2 piece set with engine hook slot) SEM-CR-718EH
Laser-cut fiber rings which center an ST-7 motor tube inside an ST-16 tube
Especially useful for making a standard engine mount for ST-18 rocket bodies
Thickness is 0.05"
I.D = 0.759
O.D = 1.8