The 8233/E55L is a power pentode vacuum tube in a 9 pin miniature envelope. It has a maximum plate voltage of 250 volts and can deliver a maximum anode dissipation of 8 watts. It has internal grid-to-plate capacitance which is ideal for use as a radio-frequency (RF) amplifier in radio receivers, transmitters, and other HF signal-processing circuits. The E55L has a very low noise figure and can provide excellent signal-to-noise ratio when used in the right application. The tube has a separate cathode connection for use when additional negative bias is required. It also has good stability, power output, and low distortion, making it a great choice for many high-frequency, low-noise applications.