Sold in pairs. The outside is waterproof nylon and the lining is 300 weight Polatec fleece. A separating zipper allows for unzipping and removing. All sizes are 13" tall, but there are 3 widths:
#116 Child - 14" around
#117 Adult - 18" around
#118 Adult XL - 20" around
Measure your calf at the broadest point, then measure it wearing any pants you might wear under the calf warmers. Heavy snow or sweat pants could add 3" to your calf measurement. Machine washable on warm with zipper closed. Dry on a towel.