1. Use upgraded internal sensors. It senses changes in the density of the space behind the wall and can locate the stud center very accurately. 2. Powerful to quickly and easily locate wood metal studs, joists, metal pipe rebar and live AC wires behind walls, floors and ceilings. 3. The design of the alarm allows you to know the situation of the wall at all times, making the operation more accurate 4. The wall detector can clearly identify what objects are inside the wall, which is more intuitive and accurate. Wood detection, metal detection, electric current detection. 5. Wide range of adaptations, using upgraded internal sensors. It senses changes in the density of the space behind the wall and can locate the stud center very accurately. Model:SH301 Product size:17.4x7.7x3.6cm Product net weight:160g Alarm Mode:Beep Battery type:9V battery (shipped without battery) Color:Black & White Material:ABS Package Contents: 1 * Metal Detector Backlit Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.