The #110 snow guard is primarily designed to be used on asphalt shingled roofs. The #110 Snow Guard is similar to the #100 snow guard but with a shorter bar. The bar on this snowguard is only 9 inches long compared to the 17" bar on the #100 snow guard. For new construction applications use two nails and caulk over the nail holes. For retrofit applications be sure to reseal the shingles with proper roofing cement.