This vintage NOS Pfanstiehl replacement needle, model M855-DS77, is designed for use with Tetrad heads on turntables from the 80's-90's. The needle features a combination of diamond and synthetic sapphire for optimal playback performance. It is a single unit in black color and is manufactured in the United States by Pfanstiehl. This needle is compatible with various models from the Tetrad product line, offering a high-quality solution for those seeking to replace their worn-out or damaged needles for enhanced audio experience.