J-Fiber High Density Fiberglass Waterproofing Membrane Fabric - 6" X 75' Roll Product Reviewers Wanted! Save $5 now and afterward write us a review of your experience. Use Promo Code: JFIBER05 Fiberglass fabric designed to work with all types of waterproofing membrane products (RedGard, Laticrete, Green Seel) Use on expansion joints and all changes of plane. Roll Dimensions: 6 IN X 75 FT (15 CM X 23 M) Excellent for waterproofing showers, bathroom walls, tub surrounds, or any high moisture areas.