The mid weight section is designed to give you the option of if you require a good mid layer fleece jacket to keep you warm, or a nice micro fleece pull over. If you are looking at a more thermal warmer kind of fleece then a full zip jacket with a higher fleece spec will be better. If you are more active in the outdoors and require a mid layer a micro fleece provides much better freedom of movement for the more active walker, Skier and snowboarder.