2/pkg-Dryer Vent Bird Guards - Bird Stop inserts - Bird Guard - Dryer Vent Grill - Pest Guard - Stop Birds From Nesting in Dryer Vent Pipes and Bathroom Vent Pipes Stops Birds Nesting In Dryer Vents and Bathroom Exhaust Vents Easy self installation - http://youtu.be/bfA-c7gxW44 No tools necessary (EXCEPT FOR LADDER IF NEEDED) Easily removed and cleaned ( recommended every 6 months) Durable polycarbonate