Features:Testing: With this tester, you can quickly find the reason why neon lamp does not turn on. Battery install: Do not reverse the polarity of the battery. Please install the batteries correctly before closing the cover. Avoid vibration: Avoid strong vibration while using, carrying, or storing. Keep this item clean. How to use: Install the batteries (pay attention to the polarity). Extend the antenna and touch it to the polarity wire of neon tube. Press and hold power button, then LED indicator and the neon tube will flash. Notes: When you touch the antenna with your hand, do not press power button, or you will be shocked. SpecificationMaterial: Plastic, metalColor: BlackFolding size(L x W): About 18.5 x 2cm/7.3 x 0.79inchStretchable antenna length: About 15cm/5.9inchBattery: 4pcs AA battery(not included)Purchasing Instructions:If you want to test tube is good or bad, the product is only suitable for the neon tube detection, this product can only detect whether tube leakage, leakage must be bad, the neon lights didn't "have a filament, measured, so the light is good, light is not bad, but ordinary lamp filament, if the filament broken, not leak tube, test out lamp will light, so ordinary lamp is mainly used to distinguish between colors, can't rely on this product to test tubes.The net weight of this product is 80g, and the shipment does not include batteries.Package included:1pc x Neon Light Tester 1pc x English User Manual