The uncertainty of dressing for cold weather base miles often means you need some mid ride flexibility. Sometimes you arms are too cold. When the sun comes out halfway through a ride, the get too warm. The Mavic Aksium Convertible Jacket's zip off sleeves let you customize your kit to suit changing conditions. A good cycling jacket provides lightweight insulation and wind protection, and the Aksium delivers the latter with its Ride Wick Warm membrane, which cuts the wind so you'll have no excuse to cut your ride short. The soft polyester fabric helps you stay warm and moves moisture away from your skin, and the ergonomic seams and stretch panels give the Aksium a comfortable, easy moving fit that won't irritate your skin or hinder movement. When you get a little warm, you can quickly unzip the sleeves and stash them in one of the three back pockets. There's also an additional zippered chest pocket for your phone or wallet. The details include an asymmetrical zipper and soft fleece lined collar to prevent chin irritation, and a ton of reflective highlights for increased safety. The Aksium's Ergo cuffs seal around your wrists to lock out drafts, and the silicone band at the hem stops the jacket from riding up and exposing skin when you're in an aero position.