Check the listing for details. POLAR Adjustable Zipper Cooling Vest with (5-12) Kool Max® Packs 4.5" x 6". Condition: Used. Listed at 135.00 USD. The POLAR Adjustable Zipper Cooling Vest is engineered to provide effective cooling relief during hot conditions or intense physical activity. Featuring an adjustable zipper and sizing options, the vest fits a wide range of body types comfortably.