Black & Decker BM3B 6V and 12V Battery Charger / Maintainer
Lowest price ever on Amazon.
$11.63 + Free Shipping for Prime Members
Amazon Rating – 4 out of 5 stars with 2,442 reviews
https://www.amazon.com/Decker-BM3…maintaine
Also
Walmart
$11.63 with in-store pickup ($15.49 – $3.86 store pickup discount)
Walmart Rating – 4+ out of 5 stars with 171 reviews
https://www.walmart.com/ip/Black-…r/21721663
Info:
Battery Maintainer for use on 6V & 12V battery systems.
Charges 6 and 12 volt AGM, GEL and WET batteries
Easy connection to vehicle battery using the included battery clips, O-ring terminals or vehicle DC plug
High-frequency smart charging technology keeps batteries at optimal charge
Automatically switches between charging mode and float mode monitoring
Built-in mounting bracket