Use on roof pitches from 3/12 to 20/12. Helps remove excess heat and moisture to protect against premature roof deterioration and helps prevent problems with birds, insects and animals in attic. Prevents roof rot in attic or roof deck. Minimizes peeling and extends the life of exterior and interior paint. Limits mold growth. Easy to install, shingle over design is virtually invisible when installed. Includes "Smart Nails" for hand-nailing, or 1-3/4" coil nails for nail guns. Meets or exceeds all code requirements. 16.9 sq. ins. per linear foot of net free ventilating area when hand-nailed. 14.1 sq. ins. per linear foot of net free ventilating area when using nail gun. Will not crack or dent during installation. Won't corrode, rust, or turn brittle. Works with traditional size ridge cap shingles.