Victor Ultrasonic Pestchaser
This repeller works with variable high-frequency sound waves in average-size rooms (variables include dense furniture and objects). The the sound is disturbing to rodents and the noise is inaudible to non-rodent pets. Infestations should subside after six days. Mice do not stay inside wall spaces but leave to feed, and this ultrasound will affect them when they do, encouraging them to leave the house.
M. S. Global Direct
This multi-use repeller works against rodents including squirrels. This plug-in model is safe for use around non-rodent pets. Changing sound waves in the frequency of 45,000 Hz agitate and repel mice from the home. The variety of noises and intermittent intensities prevent habituation while enhancing rodent dispersal. This repeller is not for use in rodent pet households, as it repels up to 2,000 square feet once in operation. No repeller needs to work just in the wall, as they are designed to create an overarching inhospitable environment for mice.
Ultimate AT
This high-level economic repeller is plugged in an outlet and has several settings for the best use. The settings are for ultrasonic, electromagnetic and ionic repelling. This repeller cannot be used in rodent pet households, as its ultrasonic pulse reaches 5,000 square feet. The sound is created by a ceramic transducer that increases efficacy and range as it agitates and disturbs mice and other rodent species. This device works by preventing mice from using the majority of the house space, but can work in walls if directed into the wall space. Identify wall space runs by listening for scurrying activity and looking for access points (holes in the wall littered by droppings). Cut a hole into that area of the wall and insert the device to emit sound waves in the area.
Agrizap
This repeller is intended for open square footage use in commercial buildings, agricultural areas or in homes. This device has speakers that cover a 180-degree sound range. It is a plug-in device which sends an ultrasonic frequency through reasonably dense areas and covers up to 1,000 square feet.