Maintains contact with minimum pressure. Aquasonic(r) 100 Ultrasound Transmission Gel is water-soluble, hypoallergenic and nongreasy. An acoustically correct medium for a broad range of frequencies used in medical ultra-sound applications. Unlike other gels, Aquasonic(r) 100 requires a minimum amount of pressure to maintain contact. Spreads quickly and evenly. Gallon jug is packaged with a smaller bottle for easy dispensing.