Gutterglove Stainless Steel Micro-Mesh gutter guards carrying the UL Mark are certified through UL Solutions to be compliant as Rainwater Catchment System Components. They have been tested and are classified in accordance with NSF Protocol P151 and NSF/ANSI 372. Modifications made to any materials or components, including painting, WILL VOID the manufacturer’s warranty, can nullify the ability of the product to act as a Rainwater Catchment System Component, and may negatively impact the drainage performance of the gutter guard.