Bright orange and hard to lose. This Hi*AF rechargeable 510 thread battery stands out in your pocket, bag or car. It works with 510 thread cartridges, the most common cartridge fitting around. Charge it fully before your first session. Its loud color makes it easy to tell which battery is yours when a few are sitting on the table. Keep it out of hot cars and direct sunlight. Wipe the contact gently with a dry cotton swab if you notice any residue.