Unique drive belt is released together with TA05-IFS R Chassis Kit which can used as a supplementary gear the drive train (37T-18T-37T pulleys). It's also coupled with TA05 show drive train (36T- 16T-36T pulleys) if improvements suggested in TA05-IFS R guide are followed assuming ITEM 53988 Ball Differential Pulley (37T) and either ITEM 53989 Center Pulley (18T) or ITEM 54050 TA05-IFS R 18T Center One-Way are arranged.