Offered is a lot of (5) type 56 Triode Tubes by Sylvania. The tubes each test good with robust readings, they show no shorts or inter-element leakage. The tubes have black plates and side getters with all good silver flashing. Production codes are as follows: 2NZ, E8R, F5R, H7R and D6R. (2) have green-printed lettering and (3) have hot-stamped base graphics. These types are popular for audio use nowadays-they are similar to the often-used type 27 triode but these have higher transconductance and amplification.  Pick them up for your own audio amps or for radio repair. 1930's vintage. NO RESERVE!! Thanks for looking.