The Model 400, 401, and 537 Strobe Light Replacement Flashtube is a practical solution for replacing your existing flashtube. With its white housing, this replacement flashtube is sold individually and is made in the U.S.A. It is designed to fit most J.W. Speaker 400 and 401 strobe lights, ensuring compatibility and ease of use. Upgrade your strobe lights with this reliable and efficient replacement flashtube, offering a convenient solution for maintaining optimal performance.