Part Number 587B151 is a Transient Suppressor manufactured by ProTek Devices. Its Description is a UNIDIRECTIONAL, SILICON, TVS DIODE 120 volt 15 amp with a plastic package-4 Current Status is Active & Available from Electronic Supply Chain Solutions a ProTek franchised distributor. The ProTek Devices Surge Buster Modules are available from ESCS with a description as follows: The 587B Series of 120 Volt AC Surge Suppressors is designed for use by the OEM, equipment installers and or maintenance contractors. These modules distributed by ESCS employ a three stage technology proven to be the most cost effective and reliable method in protecting sensitive electronic equipment from over voltage transients. This series is designed to protect AC powered equipment from the 6,000 Volt peak open circuit voltage and 3,000 Amp short circuit current as defined in ANSI/IEEE C62.41, Category CI. The 587B Series offers a high degree of protection against 120 VAC line noise. It is ideal for protecting 400 Volt components because the solid state TVS technology assures that the line-to-neutral voltage will not exceed 400 Volts. While the modules are designed for transient voltage protection, the advanced circuitry will also attenuate the amplitude and slow the rate of rise of high frequency noise. The 587B Series includes differential mode and common mode protection, which is effective in reducing interference from line to equipment and are effective in reducing equipment generated noise to meet FCC, VDE and CSA interference requirements. Contact your ESCS representative for more information.