Rat / Mice Deterant Devices (Crofton WF4)
Emits a high frequency sound (can be heard slightly if you are close to it) that is supposed to deter mice and rats, I can't say if it works or not as I think we have managed to get rid of them without trying these out but they are in working order. Require 6x AAA batteries and so can be used outside where there are no power sockets.
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