The Intelect Legend XT/ Intelect Transport UltraSound Applicators are waterproof, so it can be used with gels and other diagnostic tools. It is also pre-calibrated for precision and accuracy. These applicators operates at 1 MHz and 3.3 MHz frequencies. These sound head applicators are interchangeable with electronic signature recognition residing in all transducers. It is ergonomically designed and so will fit easily in the hand without causing aches and pain with prolonged use. The Intelect Legend XT/ Intelect Transport UltraSound Applicators are great addition to any therapy unit because it is versatile and it is recommended for use by clinicians. These sound applicators are readily available and easy to ship.