AC2® Premium decking has been pressure treated for above ground (AG) applications. It is wane-free, has more clear wood, has a maximum knot size of 1-1/2-inch (vs. standard or #2 decking at 2-1/2"), and has through holes that are a maximum of one per 4 feet of length (vs. standard or #2 that can be scattered). AC2® brand treated wood products use MicroPro® technology, which is a revolutionary way to pressure-treat wood for decks, fences, landscaping, and general construction uses. MicroPro® technology offers many benefits, including significantly improved corrosion performance, a lighter, more natural color, and it is environmentally friendly. Wood is a natural product with many unique characteristics and properties. While wood's strength and workability make it highly suited for general construction and building projects, other inherent characteristics make it subject to checks, splits, warps, and twists.