The linksys re4000w wall plug simultaneous dual band wifi range extender allows you to easily boost the range of your existing wireless router and create a strong reliable wi fi signal for laptops and smartphones in your home this linksys re4000w wi fi range extender delivers a coverage area of up to 7 500 square feet by repeating and redistributing the signal from the router to eliminate dead zones this linksys re4000w wi fi range extender is universally compatible with all internet routers