The rodent sirens Bionic Ultrasonic rodent siren against mice and rats, martens and the like. Emits ultrasounds and can be set to reproduce cat and mouse sounds which enhance the scare effect (bionic). Covers up to approx. 600 m2. Only works when connecting the included 9V adapter to 230V. From 16-50 KHZ. Beautifully designed wooden cabinet. Stepless 5 points. adjustment of output. 23 x 14 x 12 cm 1-3 = low frequency - largest animal. 3-5 = medium/higher frequency - least expensive. Red button = Bionic effect, recommended for use at night, when mice and rats are most active and where the sound does not bother people. In this way, you get a more effective guard dog against mice and rats, also in larger areas such as shop premises, garages, warehouses and the like.