Store SBR 3.9" x 29mm Centering Rings $4.29 SBR 3.9" x 29mm Centering Rings $4.29 Model Number: CR429 Maximum quantity exceeded Minimum purchase amount of 0 is required Maximum purchase amount of 0 is allowed 4.290 10000000 Categories: Parts and Accessories Manufacturer: SBR High Powered Model Rockets Description 3.9" x 29mm Centering Rings, laser-cut 1/8" plywood