Heavy Duty Low Profile Half Slotted Strut Channel (Holes are 1-1/8 inches long, 9/16 inches wide and 2 inches center to center.) strut channels for framing and mounting applications. The gold colored zinc dichromate is applied over the electro-galvanized surface to produce a chemically-bonded, nonporous surface barrier. This provides protection from moisture and air and to provide an excellent surface for painting if desired. The gold finish also provides a low electrical resistance when the system needs to be grounded.Material is 12 gauge (0.105 inch) thickness.