This collar is designed to let pets see from side-to-side, but prevents them from licking or biting wounds. Top Performance® Elizabethan Collars prevent pets from reaching and irritating wounds to promote faster healing. Made of flexible, translucent plastic, collars allow pets to maintain peripheral vision. Velcro® neckline and outer rim are padded with felt to prevent chafing. Collar Sizes X-Small through Large have Velcro® tabs to adjust fit. X-Large and XX-Large sizes have metal snaps. Collar Size Cone Size Closes with: X-Small 8" 5 1/2" W Velcro® Small 10" 5" W Velcro® Medium 11 1/2" 5 3/4"W Velcro® Large 12 1/2" 5 3/4"W Velcro® X-Large 12" - 17" 8"W 3 rows of snaps. Each row has 3 snaps that allow you to adjust the diameter. XX-Large 14" - 20" 10"W 3 rows of snaps. Each row has 3 snaps that allow you to adjust the diameter.