Polylok's 24" Pipe Ring can be cast into a concrete slab up to 6" or fastened to Polylok 24" Risers, 24" Riser Pan, 24" Riser Adapter Ring, and 24" Riser-to-Riser Adapter Ring. The 24" Pipe Ring is heavy duty and allows 24" corrugated, 24" PVC ribbed, and 24" smooth wall pipe to be attached by using stainless steel screws and expanding foam.