1S 3.7V 10A 6MOS 18650 Charger PCB BMS Protection Board for 18650 Li-ion Lithium LiPo Battery Cell (10pcs)

Used this to update an old electric screwdriver to use an 18650 battery. Works great.

They do there good for how long don't know but great price.

bought these for my projects as I mess with a lot of unprotected lithium cells of various types and wanted something that could take 10a as the 4a versions were often too weak for my deviceswhen soldering like most of these kits there is a square of nickel bonded to the battery terminalsit is meant for nickel spot welding ease when building parallel packs but I warn you if using an unprotected polymer pack as a source with existing wires you might want to pre-tin the pad and wipe off the nickel squarealso I once had a similar product that I heated so much it lost one of the resistors so be careful when soldering to prevent heating the entire thing hot enough to have bits fall off

I bought this item and used it, it fried on a single cell and a 9 parallel bank. fried instantly.... Even with a heat sink.

Works fine up to 8 amps. Small powerful little units. No complaints