Radio Gear, Battery and Charger, Possibly an ESC Upgrade and a Motor and PVC Tyres..

Small hop ups like a Ball bearing kit and alloy propshaft are all that is Needed..

If You Buy a Kit, it may not come with an ESC, Motor or Radio Gear ..

If You buy it as RTR called an XB Pro TT-01, then you will only need Battery and Charger with the hop ups mentioned..