The Telefunken Phillips Raytheon 5840W Vacuum Tube with PCB Mount is a premium USA-made vacuum tube designed for use in Telefunken TF47 microphones. This sub-miniature pentode tube offers low noise, low microphonics, and a full, even tone, making it a great choice for Class-A and Class-AB circuits. Equipped with a PCB mount; it can be easily installed without soldering..