I purchased a 38mm motor adapter for use with my LOC Doorknob. This is a very simple component and the parts fit just as they should. I sanded away the laser burn edges of the plywood and also peeled the glassine from the tube in order to get a really good epoxy penetration into the tube. Assembly is a snap, and it works very nicely. Note that if you are building this after having the MMAS fully built and installed on your rocket, make sure to not glue the upper ring without sliding the adapter into the rocket. You will want to be sure that the upper ring is in contact with the thrust ring of the MMAS at the same time that the bottom ring contacts the bottom of the rocket. This results in the thrust loads being shared by both the bottom and top rings of the entire MMAS system.