Why Choose UsWe have our own factory, and this dog life jacket is made by ourselves. We take part in all procedures, material selection, dyeing, production and quality inspection. We always try to do our best in all steps, do everything to satisfy our customers. We have a professional operation team, we can serve your problem timely and efficiently.Dimension X-Small Body Length: 7.9 inches Neck Girth: 12.6-13.8 inches Chest Girth: 14.2-16.5 inches (Most Important) Recommended Weight 2.2-13.2 lb.Small Body Length: 10.6 inches Neck Girth: 13.4-15.0 inches Chest Girth: 17.3-21.3 inches (Most Important) Recommended Weight 13.2-17.6 lb. Medium Body Length: 13.0 inches Neck Girth: 16.9-19.7 inches Chest Girth: 21.3-25.2 inches (Most Important) Recommended Weight 17.6-48.5 lb. Large Body Length: 15.7 inches Neck Girth: 18.9-21.7 inches Chest Girth: 24.4-29.1 inches (Most Important) Recommended Weight 48.5-61.7 lb. X-Large Body Length: 17.7 inches Neck Girth: 21.3-23.6 inches Chest Girth: 28.3-31.9 inches (Most Important) Recommended Weight 61.7-88.2 lb. 2X-Large Body Length: 19.7 inches Neck Girth: 24.4-27.6 inches Chest Girth: 32.3-36.2 inches (Most Important) Recommended Weight 88-110 lb.TIPS1. This is a high-performance dog flotation device for boating, water sport adventures and activities with dogs. Designed to protect your dog while allowing them to enjoy the water and provides an easy method of retrieving your dog if an emergency arises. 2. Please allow little color different from the picture shown due to the different screen of display or reflecting light. Please allow 1 inches measurement error because the size is measured by hand.3. A note about sizing: all pups are unique and special, especially yours! Sizing guidelines may d