The Big Frog Water Heater Pre-Sediment Filter Unit is a reputable and reliable way to prevent sediment and scale issues often present in certain water conditions and water heaters. Protect your investment in a tankless or standard tank water heater! The Big Frog Water Heater Pre-Sediment Filter Unit is easily installed at the beginning of any water heater and works to keep out sediment, silt, dirt, and rust. The Big Frog Water Heater Pre-Sediment Filter Unit covers both tankless and traditional water heaters when it comes to expensive repairs and replacements The Big Frog Water Heater Pre-Sediment Filter Unit covers both tankless and traditional water heaters when it comes to expensive repairs and replacements. The Water Heater Pre-Sediment Filter Unit reduces the reoccurrences of heater repairs and replacements by putting an end to sediment, scale, and corrosion materials. Easy to read gauge that gives an alert to change the filter. Simple and quick install. Protect your Rinnai, Rheem, Noritz or Navien Tankless Water Heater by preventing scale build up.