A device comprised of either a used toilet paper or paper towel roll and dryer sheet, (ex. Bounce). You blow marijuana smoke through one end and out through the other to purify the smell of the smoke. Extensive means including excess amounts of sheets and rubber band and seals can help create a VERY efficient tool in covering up the smell of marijuana smoke.
Jim blew his hit through the Durger at his desk in him room. His parents had no idea he was smoking. The Durger covered up the stank.