BUF16821 appears to be a product code or model number rather than a distinct brand. After searching industrial supplier websites like Grainger and Radwell, no direct information about 'BUF16821' as a brand was found. However, similar alphanumeric codes are often used by manufacturers like Texas Instruments, ON Semiconductor, or STMicroelectronics for ICs (Integrated Circuits) or industrial components. If referring to a specific product, it likely belongs to the electronics or automation sector, possibly as a buffer, driver, or interface IC. For accurate details, the manufacturer's datasheet or a distributor's catalog (e.g., Mouser, Digi-Key) would be required.