An assembled rear wheel including the motor ( 48V 750W ), rim, and spokes. Does not include tire, tube, brake rotor and freewheel. 26 inches is suitable for SN100, SJ26, and Reindeer. 20 inches is suitable for SX20, SF20, SF20H, SK20, and Kangaroo. NOTE: The motor plug is a new version ( 9-pin ). Before purchasing, please check if the original motor plug is a 9-pin plug. Installation Direction: please keep the brake rotor on the left and the freewheel on the right; the motor cable side doesn’t matter. All accessories are non-refundable and non-exchangeable.