SS-R-501D, FEDERAL SPECIFICATION: ROOFING FELT, ASPHALT PREPARED, SMOOTH SURFACED (18-JUL-1985) [S/S BY ASTM-D2626 AND ASTM-D224]
SS-R-501D, FEDERAL SPECIFICATION: ROOFING FELT, ASPHALT PREPARED, SMOOTH SURFACED (18-JUL-1985) [S/S BY ASTM-D2626 AND ASTM-D224].