Woedpez Black Battery Conversion Adapter Sleeve for 18650 to 21700 Cylindrical Battery Holder Box Conversion Tube

Perfect for use in a wide range of electronic devices such as high performance flashlights and portable portable power supplies.
18650 to 21700 battery conversion cylinder, a practical solution to upgrade power sources without the need for new batteries.
Essential accessory for your energy needs on the go.
Made of plastic and metal, for long term use.
Convert your existing 18650 battery to the larger 21700 size.