NITECORE Intelligent 21700 Battery System - MPB21 Kit
Amazon.com: XTAR 21700 Battery Charger VC2L 18650 Charger 2 Slot 2022 Version with LCD Display Max 2A Rechargeable Liion and AA Charger Not Included Any Batteries(VC2L) : Electronics
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NITECORE UI2 Dual-Slot USB Charger, for 18650, 21700 etc Batteries
NITECORE UI1 1 slot USB Battery Charger for 21700, 18650 etc