Brimar describe the 6CL6 pentode valve as a video power device capable of producing 2.8 Watts of broadband video in single ended class A. This would be a bandwidth of 5.5 MHz and the anode load resistance is quoted as 7,500 Ohms.
The valve will also perform well as a single ended high gain audio amplifier, again with 2.8 Watts output and a distortion of 8%.
Looking along the grid axis, the ends of the anode are rounded. The working faces are flat and parallel to the cathode.
The Type is etched into the glass. The valve is marked as Foreign and probably is of American manufacture. See6AQ5A for the same style of etching on an RCA valve.
The thin glass tube envelope is 21 mm in diameter and, excluding the B9A base pins, is 58 mm tall.