This gutter cover is manufactured by Gutterglove, the leader in pro-install-grade DIY gutter protection systems and rated highest by leading consumer reporting media throughout North America. Stainless Steel Gutter Guard performs as good as or better than professionally installed gutter guards and at a fraction of the cost. Stainless Steel Gutter Guard is UL Certified for NSF P151 and NSF372 for rainwater harvesting systems.