Grade 6061-T6 aluminum. Stringers 1-1/4"W x 1-3/4"D. Rungs 12"W x 1.030"H x 1.442"D. Overall ladder width 14-1/2". Step distance 12". Maximum continuous length 20' 0". Drawing 805-1360280. Please specify overall length and bottom rung position (distance from bottom of ladder to topside of bottom rung). Ships in 1-2 weeks after receipt of order.