Product Description Louisville Ladder stabilizer Fits extension and single ladders with rail up to 4'' by 1 3/4'' Designed for added stability. From the Manufacturer Fits extension and single ladders with rail up to 4” x 1 3/4”. Holds 12 inches from wall and spans 48 inches to clear most windows. Stabilizers attach with 2 U-bolts and feature replaceable extra heavy duty rubber tips.