Castelli made their Lycra Shoe Covers for those cool weather race days when shaving seconds is as imperative as keeping the temperature of your feet carefully regulated, though neither are mutually exclusive of the other. Their lightweight construction urges you to wear them whenever you desire to achieve a maximum performance or aesthetic effect.The Lycra Shoe Covers are of course, made of Affinity Lycra, which is a super-lightweight and highly elasticized blend of nylon and spandex that sits flush against your shoes, but isn't an absolute bear to get on or off. Affinity even serves as a basic insulatory measure on those cooler morning rides, and is breathable enough to ensure you won't have to stop to remove the covers when the sun finally warms the roads. However, we still wouldn't recommend these covers for long winter training days -- they're just not quite thick enough for that. Castelli recommends using them within mild or warm conditions with temperatures ranging from 14 degrees Celsius (57 degrees Fahrenheit) to 22 degrees Celsius (72 degrees Fahrenheit). The presence of a camlock zipper at the rear of the Shoe Cover means you'll never be struggling into or out of this bootie. The Castelli Lycra Shoe Cover comes in your choice of Black, Red, or White to best match your favorite kit. Sizes are available from Small to XX-Large, so you're certain to find the right match for your shoes.