Thank you for viewing our products. Instant purchase is welcome. Thank you. Model Number: YF-980 / Package: Blister Pack Body Size: Approximately 26mm x 29mm x 160mm / Weight: Approximately 135g (including batteries) / Body Color: Black Batteries Used: 2 x AA batteries (sold separately) / Battery Life: Approximately 0.5 hours / Water Resistance: IPX7 class (completely waterproof) Light Source: 1 UV LED / UV Intensity: Approximately 11mW/cm2 (measurement distance 20cm) / Wavelength: 365nm * Press the switch until you hear a "click". Do not leave it on continuously. Do not look directly at the light source. It emits strong UV light, which may cause blindness or eye damage.