The Milwaukee Tool M12 Heated TOUGHSHELL Vest is designed to deliver heat built to outlast with 80 percent more stretch and five times longer life than previous generations. The re-engineered materials offer better mobility and flexibility while maintaining their heavy duty durability. With enhanced garment constructions and optimized interior liners, the heated TOUGHSHELL program adds comfort, mobility, and protection. The warm insulation and DWR-coated material offer wind and water-resistant solution for protection from the elements. Powered by M12 Redlithium battery technology, the vest features a battery-pass thru pocket design that allows for front or back battery placement, providing the versatility and comfort needed depending on the situation.