Each gate requires 4 standard AA batteries for power. Both units power on and communicate with each other properly. I played around with it and ensured that the beams turn on, that the unit responds to buttons, etc and all looks to be OK.
PLEASE read the user manual before trying to set it up, it explains everything and I have run through it many times to set the unit up and test it. I've aligned the lasers to a level surface in my home, you may need to align them again based on where you use the unit, but aligning them is NOT hard to do. You need a small flathead screwdriver for the starting gate adjustment and a 2.5mm Hex Key for adjusting the finish-line lasers. It's VERY easy to do if you actually read the user manual, otherwise if you need help Traxxas can probably walk you through this.The unit does not include the optional WiFi adapter, I'm assuming it plugs into one of the expansion ports on the starting gate. Traxxas DTS-1 Drag Timing System in Box. Powered by SixBit's eCommerce Solution.