... transmission -plug and play smart connection -Removeable lithium battey Stainless steel headband 2.4G Digital Wireless Headset 2.4 G ... ,Plug an play with 3 seconds instant reaction. Retractable stainless steel headband designFoldable and shrink design, ease to carry .Simple ... headband design,comfortable to wear,built-in the stainless steel head beams and Wrapped with the Green rubber material, ...