BTW they are regulation sized ones. One of my mouse books had the measurements.
Quoted from AFRMA website which can be found here: http://www.afrma.org/pp_mseboxes.htmMaxey Cage
For those that have asked, "What is a 'Maxey' cage?" it is the National Mouse Club's show box for mice designed by N.M.C. founder Walter Maxey. I've included a diagram from the book Exhibition and Pet Mice by Tony Cooke, L.R.I.C. They use 2 versions: one is lidless, and one is lidded. Some exhibitors will transport their 'Maxeys' in a ventilated traveling box which holds several show cages. They are painted Middle Brunswick Green on the outside and Signal Red on the inside. Walter Maxey was a postman and had access to free red and green paint because the mailboxes were painted those colors. These colors were adopted in 1904 and remain in use since.