This Bosch Digital Detector is a handy tool for locating hidden wires and pipes behind walls. With two separate LED displays, you can easily identify live cables and metal objects. The traffic light system highlights areas to avoid drilling. You'll hear when you're close to objects with the warning sound so you can avoid mistakes. Good to know- Auto-calibration means the device is ready to use right out of the box- It can detect metal objects up to 70 mm depth, ideal for thorough home inspections- You'll be able to detect live cables up to 50 mm depth for safer DIY projects- It comes with three 1.5 V LR03 AAA batteries