This VEX Servo Mount will attach the VEX 393 motor to a TETRIX hole pattern. Download the zipped package, and you will get an OBJ, STL, and STEP file.
To attach the motor, put three 8mm nuts in the holes on the low face of the mount. This will allow the mount to be attached to your robot. Attach the VEX motor with two screws (inserted from beneath the thick portion of the mount).