3600 Series W-Wheel (6mm Bore, 29mm OD, 10mm Width) - 2 Pack

W-Wheels are purpose built for two primary applications.  The outside edge has a 45 degree chamfer to align with the inside groove of goRAIL.  The inside of the wheel has a V-groove to align on V-Guides, but will work on any square edge given the wheel is held at the proper angle.