Money detector pen, anti-counterfeiting pen,UV pen,Universal Counterfeit Money Detector Pen,MOney tester pen,Invisible ink pen Features: 1) Ink visible only with pen light 2) Also may be used as a flash light 3) Batteries: AG3 x 3 4) Choking hazard: small parts, not for children under 5 years old 5)You also can use the pen to detecting money,