Features: 1. Compact and portable: being so mini and light-weight, this product does not take much space and can be easily taken away. 2. Durable material: This product is made of high-quality material, durable, long service time, firm and stable in use. 3. Cable test: Accurately test whether a single network cable transmitting signal normally. 4. Entity button, sound feedback, concave convex design, touch feedback. Humanized design to improve work efficiency. 5. LED Night Lighting: LED flashlight lighting function is convenient for line checking construction in dark environment. Description: High performance and great reliability, durable replacement for the old or damaged one, no longer need to worry about not finding the right accessories. Specifications: Measuring range: -70+3 Size: 131*40*19mm Working temperature: -10 to +60 Storage temperature: -25 to +70 Power supply: built in 900mah lithium battery (rechargeable) Automatic shutdown time: 10min Battery continuous working time: 120h Color: black Package Included: 1 * Optical Power Meter Notes:1. Please allow 0-1 inch error due to manual measurement. Thanks for your understanding.2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from real object.