The 4539-012 is a 1-1/4 inch ball check valve with a true union design, manufactured by Spears. With its socket and slip-fit female ends, this valve ensures reliable and efficient flow control in your plumbing system. Its durable PVC construction and non-threated configuration make it suitable for various applications. Easy to install and with a high-quality design, this ball check valve is a dependable choice for your plumbing needs.