Kart Smarter's Ever-Charge is a 12v Data Logger Power Adaptor. One side plugs in to your kart's on-board 12v battery, the other side connects to the expansion port on your MyChron.
MyChron 5 users can power and charge their MyChron 5 while the Ever-Charge is connected, as well as display their kart's on-board battery voltage on their MyChron screen.
MyChron 4 users can power their data logger using the Ever-Charge.