This compact handheld detector helps you locate hidden objects under nonmetallic surfaces quickly and reliably, so you can avoid drilling into support columns, rebar, or other embedded items during installation or repair. Key benefits: - Detects hidden objects under surfaces to reduce the risk of damaging structural supports during drilling or cutting. - Simple, repeatable testing procedure that lets you mark and confirm object positions with a pencil for accurate placement. - Lightweight and portable design for easy handling and on site use. How it works: - The instrument senses changes in subsurface density that alter the detector frequency, causing the indicator LEDs and audio cues to respond when a foreign object is present. - When the LEDs illuminate sequentially and all LEDs light while the unit emits a dripping sound, the device indicates the approximate location of the object under the surface. Main features and performance: - Detection depth up to 19 mm below the surface of a uniform object. - Detection error of plus or minus 3 mm. - Minimum detectable object area of 1200 mm2 to ensure reliable response. - Powered by a 6F22 type 9V battery, which is not included. - Compact dimensions of 145 x 62 x 25 mm. - Net weight approximately 71 g without battery. Operation overview: - Press and hold the power switch and slowly move the detector along the surface to be tested while watching the red indicator LEDs. - When the unit detects an object, the LEDs will light in sequence and then all light together while the unit produces a dripping sound. - Stop and mark that position with a pencil, then release the power switch and place the instrument on the opposite side of the surface. - Approach the marked position from the other side while holding the power switch, and mark again where the LEDs and sound indicate the object center. - Repeat the test several times to confirm accuracy. - If an alarm is produced under the middle area, that indicates a support column or other foreign object beneath the surface; if there are no metallic or other foreign objects, the unit will not flash or emit sound. Typical applications: - Locating wall studs, support columns, or embedded posts before drilling or mounting fixtures. - Checking ceilings and walls for hidden fasteners, anchors, or metallic inclusions before cutting or routing. - Verifying subsurface conditions in renovation and light construction tasks to prevent accidental damage. Package contents: - 1 detector unit without battery. - 1 user manual. - 1 shipping carton. This detector offers a straightforward way to find subsurface objects with clear visual and audio cues, compact size for easy carrying, and repeatable results when used according to the instructions.