ZUCA ZuZuca Pet Carrier Insert Bag - Houndstooth Black, Houndstooth Pink, or Best in Show This Pet Carrier Insert Bag must be used with a Zuca Sport Frame (sold SEPARATELY in 10 different colors). Keep your pet safe on the road by securing the Zuca Pet Carrier with a standard car seatbelt, it winds around the frame, plain and simple. Dual wheel system climbs stairs and curbs with ease, for a comfortable ride for Pup. The Zuca Sport Frames built-in seat accomodates up to 300 lbs. Flashing LED wheels for better visibility at night. Adjustable Interior Leash keeps your pet secure while leaving him plenty of room to lay down  the bag is a cozy bed to nap in too.