Ladder Stabilizer Standoff Brackets with Silicone Elbows (Sold in Pairs) Standards Compliance - Meets all ANSI and OSHA requirements for ladders up to Type 1A, 300 pound duty rating. Ladder Compatibility - Fits most aluminum and fiberglass, extension ladders with open D or O rung holes on outside of ladder rail. Hole must be a minimum of 1 Installation Method - Attaches to ladder rail without fasteners. To attach, press 2 bracket ends in, toward each other, slide ends into rung holes and release Each bracket weighs 12.5 oz constucted with aluminum tube, 31/32 outside diameter Warranty - 24 months parts and labor for manufacturing defects