Quality roofing underlayment is critical for helping to prevent wind-driven rain from infiltrating under the roof's shingles and potentially damaging the home's structure and interior. Traditional asphalt felt underlayments tear easily and absorb moisture, leading to wrinkling that telegraphs through the shingles. Competitively priced with typical #15 and #30 asphalt felts, GAF's FeltBuster™ High-Traction Synthetic Roofing Felt is virtually untearable and will not absorb moisture, helping to prevent wrinkling. Its specially designed surface combines enhanced walkability with a cooler working surface.