Plastic Oddities MV34 Roof Vent Cap Helps Keep Out Leaves, Debris, Flying Insects, Animals Used on Roof Vents & Portable Toilet Vents Fits 3" or 4" Pipe Bolts onto Pipe Helps prevent rain, leaves, debris, flying insects, animals like squirrels from entering vent pipe Works on roof vent pipe as well as portable toilet vent pipe Fits 3" or 4" vent pipe Flat end bolts safely attach cap to the pipe without penetrating, unlike pointed bolts Made in the USA