This is a handle that mounts via an M8 socket head cap screw (SHCS) or hex bolt/nut. I use it on the same that normally holds my horizontal spool roller on the top of my rostock-mini when it's in use. The handle is parametric so you can make it a different size by editing the OpenSCAD file. The two STL files provided will work with either a round SHCS or with a hex head bolt or a hex nut. Print. Attach to whatever you want to carry/open using an M8 bolt, either a hex bolt or a SHCS depending upon what version you printed. If you are using a bolt or SHCS, it should be 30mm or less to fit inside the handle. If you need a longer bolt, you can come in from the back and use a hex nut inside the handle.