Synthetic grass looks like real grass and is easy to keep clean. Simply water it like real grass to rinse away urine residue. Water and urine drain through the perforated grass instantly, keeping it dry and odor free. Our synthetic grass is made specifically for the Porch Potty to make picking up solids and rinsing easy. The grass is made from water proof nylon strands and a durable latex backing. It will last for several years. However, many Porch Potty owners replace their synthetic grass after 6 months to 1 year of use due to the accumulation of urine deposits leading to odor that cannot be removed. Longevity of synthetic grass depends on how often the potty is used, if there are multiple dogs in the household, how often the grass is cleaned and the unavoidable circumstance that some dogs have a stronger urine smell.