The KL 405 is a 12V DC linear amplifier with a maximum output power of 180W, designed for use on the 10-meter amateur radio band (or on other HF bands with the use of a suitable low-pass filter). It requires a drive power of 1 to 10W in all modes of operation. The KL 405 features a six-position output power selector controlled by a knob on the front panel, as well as a receive preamplifier with electronic switching, which can be activated via a switch on the front panel.