The Cerium Hybrid is a thing of beauty. It's an insulated and packable jacket which is ideal for any time of the year; not just the Winter.It's hybrid design means that the lofty 850 fill down keeps the body warm, while the air-permeable Fortius™ Air 50 softshell panels increase airflow. The strategic placement of different materials maximises the user benefit.The jacket also features an insulated storm hood, which uses a pull cord to bring the fit tighter to the dome.This jacket is a regular fit. I'd go for your usual size. I usually take a large in Arc'teryx jackets and a large in this style is the one.Regular fitPackable850 fill downFortius™Air 50 softshellLightweight and breathableInsulated and adjustable storm hoodLogo branding to chest and hood Arc'teryx Cerium Hybrid Insulated Down Hoody Black