Had Gutterfilter installed in late 2005. It did fine with fall leaves. Clogged in spring of 2006 with oak tree tassels. Dealer came and cleaned it for free. Clogged again spring of 2007 and now the dealer will not return my calls. Have asked Gutterfilter by phone and e-mail either to repair or provide a refund under their 20 year not clog guarantee.