This default motor is with thread, fitting for thread freewheel. If you need the rear cassette motor, the extra cost USD10 will be charged. Only suitable for Disc brake. Dropout: 100mm(front wheel)/ 135-142mm(rear wheel). 1 PCS 36V 250W/350W/500W or 48V 1000W/ 1500W hub motor with rim and spokes (Pls noted 20inch rim is not MTX brand, it’s alum alloy rim). 1 PCS 36V or 48V controller with bag. 1 PCS Display (color KT LCD8, KT LCD3, KT LED880). 1 PCS Half twist throttle (If you need the thumb throttle, please message to us). 1 PAIR Power cut off brake lever. 1 PCS PAS Sensor. Remarks: Only 20inch rim is aluminum alloy rim, not MTX rim. Only suitable for disc brake bicycle. 36V Motor wheel as below (except 20inch rim). 48V Motor wheel as below.