These are spool holders that mount on the ends of the makerslide on an ordbot. (I designed them to replace the extrusion endcaps). There are two versions of the right mount. The _pin version has a pin compatible with thing:151515. If you don't want the panel hinge pin use the "_rt" instead. ((note: this pin in thing:151515 will not fit within the walls on this thing which means you can't just glue it, you will need the _pin version, which i have not printed yet... I hit publish too soon...) The saddle at the top of each mount is 8mm and should work well with a 1/4" threaded rod. You will need to use support material when you slice the _rt_pin. I use 20% infill "linear" on each part.