How Leafproof® works
Except in areas where the roof line has concentrated water flow (such as an inside valley), water flowing off the roof does not shoot to the front of the gutter. It simply follows the roof line, on to the drip edge which is under the shingles, and down the back of the gutter. The reason that the water does not shoot to the front lip is that water clings to the surface it is flowing over. This is known as surface tension. Surface tension can best be visualized by slightly tipping a glass of water and watching the water run down the side of the glass.
Patented S-Bend Technology
LeafProof makes surface tension work for you, the homeowner. The S bend causes the water flow to reverse and churn, which slows the momentum of the water as it comes off the roof. The S bend also permits the portion of the Leafproof panel which covers the gutter, to be installed at a fairly level slope. This reduces the speed of the water even more. As a result, when the water flow reaches Leafproofs water channel, the water flow once again reverses and drains into the gutter.
There are other gutter covers on the market that work in a similar manner. However, these gutter covers do not have Leafproofs patented S bend. This means these covers must be installed under the second row of shingles and are often screwed or nailed into the roof.