Sashco 30100 Pre-Caulking Filler Rope Backer Rod， 3/8-Inch x 20-Feet， Gray<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Easy to fit - soft and pliable so it fits into the joint easily</li><li>Water resistant - unlike open cell backer rod， it repels water to help protect the joint from damage</li><li>Fills the joint so you use less caulk</li><li>Fully compatible with all substrates and sealants</li></ul></div><img src="http://ecx.images-amazon.com/images/I/51pidTckFxL.jpg" noproxy>