Popular brands of leaf filters and gutter guards include LeafFilter, Gutter Helmet and Leaf Guard. Each of these systems has cons as well as beneficial properties, according to GutterGuys.com.
LeafFilter is one of the most expensive systems available, but is supposed to have the least amount of maintenance out of the available options. The frame fits over top of the gutter and is custom fitted to each gutter. The gutter system is made of stainless steel to keep it from rusting or needing repaired. The screen on the system keeps out any particles or debris over 5/1000 of an inch. The only maintenance is that the screen may occasionally need to be scraped or cleaned.
Gutter Helmet uses a reverse curved metal to direct the water into the gutters. The principle behind this is water adhesion, states GutterGuys.com. The principle means that water will hug the curve, but anything else will slide over the top of the gutter helmet and onto the ground. This does not always happen and debris can go into the gutter still.
Leaf Guard is custom installed and is a gutter and guard system in one. It is made from a single coil of material. It does allegedly clog easier than advertised though, and must be cleaned regularly.