The printrbot chassis stretched and channeled to to fit an obscure stepper motor that they don't make anymore (nema 25?).Also: Wade extruder optimized for 6-32 hardware, and Sublime's herringbone gears (small gear fixed (no more hole in the gear mesh, thicker at the set screw), be careful on the shells on the large gear(hollow teeth= bad))http://www.printrbottalk.com/wiki/index.php?title=Main_Pageglass ends capture an 1/8" pane of glass on top of the heated board on top of a sheet of cardboard (works well enough for 1/4" too) Printrbots use .2 inch XL belt, so included is a ten tooth pulley that fits all known models (LC and Plus). My steppers have 1/4" shafts, but these are for 5mm shafts like most chinese steppers