The Pet Life ® 'Pursuit' Quilted Ultra-Plush Thermal Dog Jacket is composed of a exterior shell made of a special developed Wellon fabric that's extremely soft and silky-smooth with High-Grade Polyfill Insulation for complete warmth and comfort that when combined feels like a Duck-down jacket. Features elastic banding by the sleeveless area and across the back for a conformed tailored fit that also seals out the cold. Additionally the pursuit jacket features a unique bottom-sided zipper for convenient on and off access and folds right into an included carrying pouch that makes it great for travel. Available in Multiple Sizes and Colors. Sizing Guide - From Back of Neck to Tail area ("In" Inches) 8" - EXTRA SMALL 10-12" - SMALL 14-16" - MEDIUM 18-20" - LARGE 22-24" - EXTRA LARGE