Echogel 20Economical Ultrasonic Couplant Echogel 20 is an economical, basic use couplant in medium thick gel viscosity for ultrasonic inspections, like flaw detection sizing and thickness gauging, where salt cake or metal corrosion salts are present. It provides good corrosion inhibition and resists viscosity breakdown on salt caked boilers and other corroded materials. Benefits Enhanced surface wetting to quickly cover oily or dirty surfaces Maintains