This is an All Terrain wheel for the JJRobot Evo Self Balancing Robot ( http://www.thingiverse.com/thing:1069256 ). Thanks jjrobot guys. The standard wheels are great on smooth floors but didn't work well on carpet or outside on rough surfaces like sidewalks. Adding some rubber bands around these new wheels helps it roll on smooth floors without slipping, but not 100% necessary. The wheels are roughly the same diameter but have "treads" and are significantly wider. These wheels take a bit longer to print than the stock wheels, but are worth it if you are planning on using it in places that don't have smooth floors. Enjoy.
Wheels fit snug on notched NEMA 17 Stepper motor, same hole size as the original wheels.
March 29, 2016: I added some treads that were printed with NinjaFlex Semi-Flex. They worked out great. Created them a bit unconventionally using a bracelet OpenSCAD program, downloaded from Thingiverse I think, but I don't remember where. The "hack" was that I modified the bracket code to place the text as an extrusion rather than an indentation into the bracelet and then I changed the text to be a ">" sign for the tread and adjusted the size of the font till the ">" sign was the size of the tread. I've uploaded the OpenSCAD code and the stl file, it is a tight fit but I think snug fit is better than one that isn't. If it is too snug to fit for you, you might need to tweak the size of the bracelet.
I will post photos later.
Prints fine in PLA with 25% infill.