The EL86 is a Classic output pentode with an anode dissipation of 12 Watts which is the same as the EL84.
The difference between the two valves is that the EL86 was designed for a higher anode current with a lower anode voltage. This is an excellent audio as well as guitar valve in the correct circuit. It has been used in some transformer less designs in the audio market.
The Siemens EL86 is a very high quality EL86 that has proved one of the best audio upgrades for Graaf amplifiers. These come in the original Siemens box.