The UnderpassTM is a great little tunnel it"s a wonderful addition to your gliders cage. Hang it from the top of the cage and off they go. It"s a great spot for burrowing or taking a rest.These TUNNELS have Minky on the outside with Fleece fabric insidemade anti-pill fleecenon-exposed seams to prevent exposure to loose threads100% machine wash/dryglider safe hooks included3"diameter x 10.5"long What makes LIBBY & LOUISETM products different?All our products are made to the highest standards with your pets safety being our first priority! The materials are pet tested and approved, and all items have been constructed so they are 100% washable. I am also very proud to say it"s all made here in the USA!!!Thank you so much for looking!