Add on to your hamster habitat and hamster cage with Ferplast hamster play tubes and tunnels. The “T-Tunnel” hamster tube can be used to add a turnpike onto your hamster's tunneling system. The Ferplast hamster tube measures 5.5 length x 3.9 width with a diameter of 2.4 inches. Ferplast hamster tubes are only compatible with other Ferplast branded play tubes and will only connect onto Ferplast and MidWest Homes for Pets hamster cages. All Ferplast products include a 1-year manufacturer's warranty.