The Excursion Dog Backpack provides an excellent way to travel around town or on the trail! This easy-on/easy-off design is loaded with custom features to meet you and your pet's needs. Available in three stylish new color combination's. COLORS - ALL ITEMS ARE BLUE UNLESS OTHERWISE NOTED - If noted "assorted colors" color options include: Candy & Beet, Ice Blue & Elephant, or Red Clay & Java - Let us pick a color for you! Small - Fits Girth (19" - 24")Medium - Fits Girth (26" - 32")Large - Fits Girth (30" - 40")X-Large - Fits Girth (36" - 48") PET CLOTHING MEASUREMENT TIPS: 1. Measure your pet from the base of the neck to the base of the tail. This measurement is the length needed to determine what size of shirt, sweater, or coat is ideal for your pet. 2. Always go to the next larger size if your measurement is within 1 inch of the maximum. This is highly recommended for apparel that doesnΓÇÖt stretch such as rain gear, coats and jackets. 3. We also recommend to round up to the next size if your pet has a broad chest, bulky build or thick coat. NOTE: Somewhat loose clothing is more comfortable for your pet and looks better than tight clothing. If in doubt, order the next size larger. Outward Hound Excursion Dog Backpack - Dog Backpacks & Carriers