no circuit diagram, three wires, all red! However, I did manage to connect two, which I think works, but in fact it's a constant 12 volt block. So maybe I'm an idiot who can't tell the difference between the 3 red wires or this is a very dubious product. The next comes from HomeDepot for little money but peace of mind.
Keep Your Battery Fully Charged With A Smart 12V Charger/Maintainer Featuring Winter Mode
28 Review
Xiaomi 70mai Jump Starter Midrive PS01
120 Review
Efficient Charging With LST 7 Stages 5A Battery Charger - 3.3A 12V For Ultimate Performance
35 Review
Case Compatible With Halo Bolt Portable Car Battery Jump Starter 58830/44400/57720 MWh Charger. Power Bank Holder For Halo Power Station 100/For AC Outlet.(Not Fits For Halo Bolt Air, Box Only)
24 Review