Relefree 3aaa Aluminium Invisible Blacklight Detection Ink Marker 21led Uv Ultra Violet Mini Portable Flashlight Torch Light Lamp Brand new and high quality 21 LED UV blacklight flashlight Long service life up to 10,000 hours.Aluminium body, light weight Great for checking notes, credit cards, fluorescent inks (invisible inks), cracked glassware, or even crime scene LED Qty : 21 ultra bright LEDs.Rain Waterproof.Power: 3x AAA battery (not included)