Also added a block coolant heater for quick starts on on those cold mornings. The block heater plug is located by the rider's right foot on this 2010 FX/Nytro XTX. A block heater is a great addition that fits all Yamaha 4 stroke snowmobiles. In fact this block coolant heater is a universal fit for any 4 stroke liquid cooled snowmobile. Comes with installation instructions.