SĀFTRON Universal Pivoting Bumpers are made of durable rubber and have an extra-large 3.3″ Diameter footprint to provide secure footing on masonry pool walls and extra protection in pools with vinyl liners. Great for use in pools with curved and inclined walls. Will also take up ¾” gap between ladder and the pool wall if ladder does not abut the pool wall. Suitable for use with any standard 1.9″ OD Ladder