21700 battery cases are protective enclosures designed specifically to store and transport 21700 lithium-ion batteries safely. These cases are typically made of durable materials like plastic or silicone, which provide resistance against accidental impacts and potential damage. The 21700 battery cases feature a compact design that makes them portable, making it convenient to carry your batteries while on-the-go. They come in various colors and can accommodate multiple batteries at once, ensuring that you have a sufficient power supply for all your devices. These cases are essential accessories for anyone who regularly uses 21700 batteries and wants to keep them organized and protected.