PENTHOOM Gap Filler Foam Sealant Backer Rod commonly used for filling gaps around, door, windows, walls, between tiles, under kitchen shelf etc. This backer rod foam is durable, flexible, easy to install, fills gaps and holes and conforms to sealing applications. These backer foam rods help to fill or seal the small gaps between window shutters to stop mosquitos and other insects. Useful for sealing gaps around your window AC. This foam filler can be used as a window gap filler for soundproofing or reducing sound pollution. Please make sure to order the correct diameter based on the size of the gap. The EPE foam rods can be used to tuck and hold the elastic sofa cover in place. The ideal size for this purpose is 20mm diameter/thickness. Also useful for filling gaps between walls and aluminium frame. This gap sealer Backer Rod increase elasticity in the joint sealant and reduce caulk consumption by controlling sealant depth. This gap filler foam can easily compress and return to its initial state due to unrestricted air movement.