The Touchdog ® Onesie Lightweight and Breathable Full Body Dog Pajamas Jumpsuit is composed of soft high thread count polyester, cotton and Lycra. These doggy onesie Pajamas cover the legs and arms for a more expandable fit and comfortable sleep, fabric is also breathable. Features accented print detail along the back with a leash slit along the neck area. Machine washable. These Onesies for Dogs are Available in Multiple Colors and Sizes. 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