These are best suited for hanging as shown, rather than floors or flat surfaces (IMHO). Mine worked well in my tests and is a bit louder than some. Decent value for the price, I think. This design is a bit different than most others and well suited for hanging on a tub or basin (or whatever) to prevent overflow. Can also be used for leak detection, but the wire is very stiff, so in some situations the simpler, "just sit it down on the floor" designs are easier to use. But this is better if you need to feed the "detector" into an enclosed area or pan.