ProPest are specialists in mouse control oxford. Mice are very good at squeezing through the smallest of holes. 6mm is all a fully grown Mouse needs to gain entry into your walls cavity. The most popular hide out for mice is under your washing machine…..”WHY IS THAT I HEAR YOU ASK?… its warm, its secluded and there is very little chance of being disturbed. There is a large void underneath washing machines between the concrete and the outside wall of the machine mice utilise.