The jacket is a classic fit with many utility pockets, full fleece inner liner and barrier softshell outer which is wind and water resistant. Every vest includes a lightweight, rechargeable Lithium Ion battery, removable heating elements, external temp controller and a charger. The jacket will heat for up to 8 hours before needing to be re-charged. The optional #5698 12 volt adapter kit will allow any IonGear vest or jacket to operate continuously off of a 12 volt power source. Size XXX-Large.