Store SBR 54 to 29mm Motor Mount Adapter $11.00 SBR 54 to 29mm Motor Mount Adapter $11.00 Model Number: MMA5429 Maximum quantity exceeded Minimum purchase amount of 0 is required Maximum purchase amount of 0 is allowed 11.000 10000000 Categories: Parts and Accessories Manufacturer: SBR High Powered Model Rockets Description Use a 29mm motor in your 54mm motor mount. Laser-cut plywood parts, quality SBR tubing - easy assembly using Epoxy.