Sunnytech ZVS Inverter High Voltage Power Supply Ignition Driver Can Drive Tesla Coil M063 Stirlingtechonline is exclusive distributor and the owner of the brand "SunnyTech"----Please be sure you receive an authentic SunnyTech stirling with SunnyTech logo and only sold by Stirlingtechonline to ensure 1-year 100% Satisfaction Guarantee. it's a already finish assebmbled toy.you will receive a finised product exactly as the picture,just take it out from the box, and play.No any drilling or soldiering required. 1. Driver board does not work Please check if power supply voltage/current is sufficient. Normally recommend use 12V+, 5A+ power supply. 2. Excessive heat generated at magnetic coil When using transformer as power supply, filter capacitor should have sufficient capacity, otherwise voltage will not be stable, then coil inductor will shoulder great voltage fluctuation and gives out excessive heat. Recommend to use 10000uf+ filter capacitor. 3.Weight:400g It is a amazing and fantastic product at this price,it can be a great gift to your families or friends. It also can be used for teaching purpose. Many of our customers comes from school,colleague,etc