Industrial Rolling Safety Ladder with Platform Height 1. Once in position, the 4-wheel braking system creates an immovable anchor, ensuring the stairs stay firmly in place while you climb or work. [1213 LBS CAPACITY & STABILITY]: Engineered with premium 30x30mm thickened carbon steel square tubes (1.5mm thickness), this heavy-duty rolling ladder supports an industry-leading 1213 lbs (550kg).