Specifications: 254nm shortwave and 365nm longwave UV lamp for fluorescence detection on stamps and banknotes. Note: 4 AA batteries (not included). This longwave lamp reveals fluorescent and colored bands on GB stamps, including blue and yellow reactions. It is also effective on stamps from Australia, Canada, China, France, Germany, Hong Kong, Mexico, Norway, and Russia. The lamp can help identify different paper types such as OCP, FCP, PCP, and ACP. For optimal results, use in a dimly lit room against a dark background. This handheld portable unit requires 4 AA batteries. Shortwave lamp function: The shortwave lamp clearly shows phosphor and phosphor afterglow on GB stamps produced up to 1992. Best results are achieved in a completely dark room. To observe the different colored phosphors on the 1960 Wildings issue, look for the afterglow effect immediately after turning off the UV light. Green phosphor exhibits the brightest afterglow (10 seconds), followed by blue (15 seconds), while violet has a very short afterglow (5 seconds). Afterglow effects are difficult to observe in daylight; a dark environment is essential. This handheld portable unit requires 4 AA batteries (not included). Condition: 100% . Package includes: 1 x 365nm longwave UV lamp 1 x 254nm shortwave UV lamp