All General Rules apply
1) Must be a tagged Group 27 armature, and mass produced by a USRA. approved manufacturer.
2) Must be commercially available, as defined in General Rules.
3) Must be wound with a minimum of 38 series wound turns of AWG #27 wire per pole. AWG #27 wire, excluding insulation, is .0141-.0143 inches diameter.
4) Armature stack lamination length shall be a minimum of .440 inches
(11.176mm). See Armature Stack Length section for further clarification.
D) Wheels, Tires, Gears
Must comply with general rules otherwise no restrictions
Must be commercially available and approved for use in restricted classes