MAXTID Door Draft Stopper - When winter comes, this door draft stopper prevents the heat air from your AC system from escaping your room, simply effective in managing your heating and cooling bills! It’s also an outstanding soundproofing tool and can shut out noise and somke. It also filters out 90 percent of the sun’s rays. So they’re perfect to hang in the bedroom of a late-morning sleeper or someone who works a night shift. Our draft blocker for bottom of door not only has the function of sound proof, It also prevents cold air from entering the room.. This draft blocker stays put as it easily slides back and forth across the floor.