The 12HE7 is a miniature type dual-diode triode vacuum tube designed for use as an audio preamplifier in both high-fidelity and musical instrument applications. It is rated for a plate dissipation of 0.4 Watts, a maximum plate voltage of 250 Volts, and a maximum plate current of 20 mA. This tube has a very low noise level and a very linear characteristics which makes it ideal for audio applications. It also has a good air coupling characteristics and its low microphonics makes it ideal for use in guitar amplifiers.