BMS 4S 18A 12A 16.8V 18650 Lithium Battery Packs Charge Board Overcharge/Short Circuit Protection For Power Bank/Electric Tools BMS 4S 18A 12A 16.8V 18650 Lithium Battery Packs Charge Board Overcharge/Short Circuit Protection For Power Bank/Electric Tools. Sale price : $1.39 Category : Consumer Electronics