MagVent MV-180 Magnetic Dryer Vent Coupling For 180 Venting, or Vent pipes Exiting Straight into Wall Behind Dryer of New & Existing Construction. Utilizes Zero Flame Spread, UL 2158A Approved Dryerflex Transition Hose. Strong Magnets Self-align & Attach Dryer Hose to Standard 4 inch Wall Vent. Easy, Solid Installs that Boost Dryer Efficiency & Safety!