Helly Hansen Freeze Prowool 1/2 Zip Top - Women's 2012: The Women’s Helly Hansen Freeze Prowool ½ Zip Top is a baselayer with an attitude. The Freeze Prowool ½ Zip can be worn as a layer or as a stylish après top. The Freeze Prowool features Lifa® T3TM hollow fiber technology and Merino wool to give it a luxurious feel next to your skin. The seams are placed out of the way of high friction areas and are stitched with flatlock stitching to minimize bulk.