... : AAA , 2 pcs Power Sound sensitivities To detect multi currencies 980nm invisible light emit The ... 980nm wavelength of invisible light, can detect multi currency with Sound control Infrared(IR) Anti-Counterfeit Detctor Model : HT1 1,Detecting Theory ... cm, Weight 30 gram,DC3V,AA battery,Looks like TV control,Plastic shell (Temporarily used, if need special shell, we can ...