Others can be used on floors and ceilings. If your magnetic stud finder sticks to the wall theres a good chance theres a stud there.

Stud Finder Wikipedia
Stud finders that work. Includes a deep scan mode that can detect objects through two layers of drywall up to 1 12 38 mm. Before there were stud finders either you pounded a small nail into the wall until you hit a stud or you used a small pivoting magnet. It features an lcd. Magnetic stud finders use a very simple concept. Hanson 03040 magnetic stud finder includes a small level that you can rotate either vertically or horizontally depending on the orientation of the tool a feature that helps with locating. Large lcd screen utilizes a target indication bar to clearly locate objects behind a wall or ceiling.
The tavool stud finder features a multi scanner that can be used to quickly locate both metal and wood studs pipes and live wiring. The first technique works but it damages the wall. A stud finder also stud detector or stud sensor is a handheld device used with wood buildings to locate framing studs located behind the final walling surface usually drywall. Will also locate steel studs. Vivreal 4 in 1 stud finder and wall scanner. If you have been exasperated with stud finders in the past and prefer one that can tell you more this model may be a good option.
Detect where support areas like studs and joists are along the wall. The magnet technique is slow. All stud finders do the same basic thing. Zircon studsensor l50 with bonus level 15 in scan depth metal and wood stud finder zircon 15 in scan depth metal and wood stud finder franklin sensors prosensor 16 in scan depth metal and wood stud finder. The nails that hold studs together are magnetic and so are dry wall fixings. A stud finder is good for well finding studs you cant see.
Stud finder that utilizes a moving magnetic piston to locate studs under sheetrock plaster or tile. A wide contoured grip for comfort and ease of use provides optimized visibility and a secure hold at any angle. The magnet would help you find nails that had been driven into a stud. How stud finders work there are two main types of stud finder magnetic and electronic. Some finders provide basic detection capabilities that are good for just walls. The studsensor hd35 stud finder features a bright the studsensor hd35 stud finder features a bright easy to understand interface.
Knowing where those are is crucial so you can be sure to screw into them instead of just the drywall when youre hanging something.