If the temperature range or the sleeves of the Pro Issue SS aren't to your liking, why not go sleeveless to get many of the same benefits and warmer weather max range? With Castelli's role in sponsoring and outfitting pro cycling teams in high performance race and training gear, it is not surprising that riders and directors often have super specific requests. The Pro Issue Sleeveless is a mild to warm temp baselayer that falls in between the Prosecco R and Pro Mesh in the line-up. Developed for high output use in temperatures from 59-86°F, the Pro Issue offers a simple light layer of highly breathable fabric and comfort. Pro cyclists often use baselayers with comfort as the primary rationale. Though it may seem somewhat specific, the Pro Issue Sleeveless actually hits 2-3 season range capability, with only the hot summer months out of play for most riders. For those of us who often ride in the mountains, it could be a choice all summer when early morning starts can be closer to 50 than 70 degrees, but end in the 80's.

During such times you aren't seeking a layer of insulating warmth but something to move the moisture away from your body and help your race jersey perform. The key is staying dry, and Castelli's 3D mesh fabric offers covered waffle-like pockets that create dead air space next to your skin keeping temperature regulated, while the polyester capillary action moves sweat away. In other words, it holds warm air just long enough to keep you comfortable while staying dry. Construction-wise, as with all baselayers, the fit has to be formed to the body to ensure the fabric works as described, so there is enough stretch to be close but allow movement. Th designers opted for minimal seams on the shoulder to reduce friction and encourage light fabric movement. The form-hugging shape has a specific, flat waist section designed to lay flat under your bib and short sections. All the edges are cleanly finished for hold and comfort. One note, the neck collar has a wider opening to fit under aero jerseys.