Long wave, hand held, portable model for detection of fluorescence of stamps and tagging on currency or phone cards. Long wave UV lamps help the currency and stamp collector to identify fluorescent paper and inks. They are an important tool to verify authenticity and to check for repairs or forgeries. Long wave ultraviolet light typically has a wavelength of approximately 366nm (nanometers). Broad spectrum of long waves with peak efficiency at 366 nm for reliable detection of luminescence. 4 Watt efficiency. Requires four AA batteries (not included).