Sound Associates manufactures two types of wireless stethoscope-style headset receivers designed for professional applications, the SA1531H (single-channel) and SA1533H (3-channel). Our headsets are equipped with a sophisticated receiving circuitry with multiple receiving diodes to increase sensitivity. Also, high-performance micro speakers are utilized to give the user remarkable audio reproduction. The SA1530 series headsets are compatible with most infrared transmission systems currently in use. They are designed with a new industrial-strength chassis for added durability in commercial applications. Its advanced mechanical design ensures years of trouble-free use, while making the headset comfortable to wear. The SA1531H is designed to receive a frequency modulation of 2.3MHz. The stethoscope-style receiver is worn under the chin, and powered by a light weight lithium polymer rechargeable battery, designed especially for the Sound Associates' line of receivers.