Castelli opted to break out their warmer line into simple thermal and protective options .Leg warmers are a great choice for those cold mornings that quickly heat up after an hour or two. It is better to go out warm and protecting your joints, then remove the warmers when you get too warm. The Nanoflex 3G offers light thermal fabric that is water-repellent and blocks enough incoming air to keep you comfortable, but also carries thermal properties to keep you warm and dry at cooler temps. Castelli invented the category of water-protective thermal fabrics, and their proprietary Nanoflex is often imitated but never equaled.

The highly breathable Nanoflex fabric is relatively light weight and flexible. Castelli uses a single seam construction, with flatlock stitching on the seam and cuffs. The fabric offers plenty of stretch, but the design has also been aligned anatomically, with moderate compression.Holding the warmer in place on the thigh, dual-sided silicone gripper elastic prevents sliding down, utilizing the skin and short material. An ankle zipper allows for quick and easy removal. Rated for a 46°-64°F range, this leg warmer is a crucial component of every cyclist's wardrobe. Castelli finishes the 3G Legwarmer with sleek, subtle embossed wordmark logos.