Tunnel Tube Rat & Toy – superior quality. Designed for larger pets such as ferrets and rats. When hanging the diameter of the holes at either end is about 10cm (4″) which is big enough for even fat pets. This clips to the cage via metal clips. This item is machine washable at low temperatures and these have been put through their paces by rats up and down the country who LOVE them! MEASUREMENTS: 36cm (14″) long (excluding straps) and 10cm (4″) hole diameter. This is well suited as a toy for ferrets and will also fit 2+ adult rats at a time.