JonRocket.com's motor mount kits generally consist of laser-cut centering rings, thrust rings, motors tubes, engine hooks, and simple instructions for assempling the parts into a motor mount which may be used in your custom designed rockets or to replace the motor mounts in rocket kits. The actual parts in the motor mount kit may not be exactly the same as shown in the photograph. The engine hook may be a different style and the spacing of the motors (for multiple-motor kits) may be slightly different. If you have any questions, please contact us before ordering.