Features: Powered by 4xAA batteries(NOT Included). Bring convenience to your-life, safety- and rest-assured. Mainly used to measure gas- leakage of the lamp- tube. Suitable for all kinds of lamp- detection, a practical tool for electrician. Widely used in a variety of scenarios: lighting shop, hardware store, electrician. Specifications: Material: Plastic Batteries: 4xAA Batteries Needed(NOT Included) Length: Approx. 20cm/7.87in(NO Extension Probe-) Note: If you want to test light tube is good or bad, this product is only suitable for the detection of neon tube, this product can only detect whether the tube leakage, leakage is certainly bad, neon light no filament-, so measured, light is good, not bright is bad. And ordinary tube has a filament-, if the filament- is broken, the tube does not leak, the test out the tube will be bright-, so ordinary tube is mainly used to distinguish the color, can not rely on this product to measure the tube is good or bad. Package includes: 1x Neon Tester