This 3-in-1 style jacket has a waterproof outer shell and an synthetic insulation liner. The outer shell is made using Montbell's original waterproof breathable material, DRYTEC®. The liner uses EXCELOFT®, a synthetic insulation which has better insulating properties when wet compared to down. Either jacket can be used by itself and can be used together when an insulated weather proof jacket is required for your perferred winter activity.