Tourmaster heated jackets were born from the world of high-tech motorcycle apparel, and can now be enjoyed while touring the countryside or simply trying to stay warm around the house. These powerful heated jackets and vests include 7.4V lithium-ion batteries that give you 2+ hours on high heat that is guaranteed to keep you warmer than ever before.Synergy 7.4V Women's Heated Vest. Features: New four-level push button 7.4v design Wind-Shark soft shell breathable and treated waterproof fabric construction Microfiber lined collar and interior of vest ESO locking front zipper, front hand pockets, inside storage pocket Shock cord waist adjustment Lycra cuffs for comfortable and secure fit Three 6.5" x 2.5" heating panels lined with steel alloy fiber elements Optimum placement of heating panels, with two on the chest and one on the back Battery life ranges from 2.5 hours on high to 10 hours on low temperature setting Surface temperature ranges of 135\xB0/100%, 120\xB0/75%, 105\xB0/50%, 90\xB0/25% Includes one 7.4v 2.0Ah rechargeable lithium-ion battery and charger (packaged separately) Tourmaster Synergy 7.4V Battery Women's Softshell Heated Vest