Potomac 1/3 Zip Combat Shirt - with or without padsThis version includes the spacer pads which are made with mod acrylic which is a synthetic copolymer. Mod acrylics are soft, strong, resilient, and dimensionally stable. They can be easily dyed, show good press and shape retention, and are quick to dry. They have outstanding resistance to chemicals and solvents, are not attacked by moths or mildew, and are nonallergenic. This model features a woven, stand up collar. It specifically designed for wear