Elite cyclists know base layers are as flexible as they are necessary. Keeping you cool in summer and warm in winter, Rapha's Merino under vests wick moisture superbly and are extremely odor resistant. Any experienced cyclist knows the value of a good base layer. It will keep you cool on scorching hot cols in July and warm on freezing descents in January. A good base layer helps regulate body temperature whatever the weather, transferring moisture from the skin, and proving a vital aid to performance. Rapha base layers are made from 100% merino wool and are naturally anti-bacterial and odor resistant. Wicking moisture vapor extremely quickly, they are soft on the skin and itch-free. Rapha's merino base layers come in three styles; sleeveless, short, and long sleeve. All the seams have flatlock stitching so they won't chafe and are positioned behind the shoulders to avoid bag or bib straps rubbing while cycling. The base layers are close-fitting and cut long at the back for a better fit on the bike. - 100% merino wool