Review on Mroinge Automatic 6V/12V Trickle Charger For Vehicles, Motorcycles, Boats And More - Maintain Your Batteries With Ease! by Blake Pudic

Keeps the battery maintained/charged in my 20 year old suburban at about 13.1V, which is good for long life of a 12V lead acid battery. I leave the charger outside in the open, rain, with no issues for months now. The included connector for the battery works great for quick connect, disconnect when I use the vehicle. If I forget to unplug it, it unplugs itself just fine when I back out. It's not very good as a battery charger with very low, slow current.