Waterguard Squares Stair Treads, Navy, Set of 4 Versatile, textural squares pattern stair treads are durable enough to make a good impression for years to come Premium 24-ounce polypropylene face; non-marking, slip-resistant, commercial grade SBR rubber backing Unique ridged construction traps dirt and moisture Guaranteed against fading, rot, and mildew Suitable for indoor and outdoor use