Machined from 6061 aluminum and hard black anodized. Hard anodizing is more resistant to scratching.Fits all Horton crossbows with dial a range sight bridge or models prior to 2013. Has mil spec slots in top instead of hortons 5 for more adjustments. The side hole is also tapped for easier installation. This is not an OEM part from Horton but a custom cnc machined aftermarket rail. Comes with new mounting bolt.