Lifting Ladders Smooth sliding lower section adjusts up and down allowing bottom rungs to be kept out of the water, high and dry but ready for action. Double-rung locking mechanism secures ladder in selected position.International Dock Products Heavy-duty aluminum ladders featuring a super-strong 665lbs. per rung maximum boarding weight capacity. Available in both standard 2" depth and foot-comforting 4" depth wide rung models. The wide-style rungs measure a full 4" in depth, with slightly rounded edges and a deeply-grooved, extruded surface that ensures greater comfort and traction that provides increased stability when climbing in or out of the water. The standard 2" wide flat ladder rungs are designed with no sharp edges and feature a long-wearing, applied nonskid surface material. Crafted from marine-grade, ID SCH 40 aluminum.