A spool holder for Octave brand filament, which is sold on [Amazon](http://www.amazon.com/Octave-1-75mm-Filament-MakerBot-Printer/dp/B0083HSPH2/ref=sr_1_1?ie=UTF8&qid=1379114731&sr=8-1&keywords=octave+filament). Contains a shaft and washer, both with holes for a 1/4 in. dia. bolt. While it is designed for a Lulzbot AO-101, it should work on any printer that has a ~ 1/4 in. hole. * Shaft Diameter: 1.2 in. * Shaft Length: 3.6 in. * Washer Diameter: 2.3 in. * Hole Diameter: 0.25 in.