Anode Cap Fits 3-500z, 3-500zg,4-400,4-400a HIGH EFFICIENCY

Came across a YouTube video showing the cooling efficiency of this plate cap vs a standard cap. I was concerned about the 3-500ZG in my SB-1000. Good tubes are not cheap and I wanted to protect the one in this amp. I spend a good amount of time on 40 and 80 meters and run the amp pretty hard (especially when running digital) so I watch the tube color pretty close. I changed to this anode cap and notice the cooldown is faster as well as the operating temp. This amp does not use a chimney so I am trying to hedge my bets by adding as much cooling as possible without amp mods. Anyway you can extend the life of a tube is usually worth it.

Installed these in a Viking Thunderbolt linear using (2) 4-400A tubes. Was concerned about height interference, but these are actually lower in height than the original factory caps and fit fine. A little tight fit on the caps, but moving them back and fourth on the tube cap made more clearance so thermal compound could be put in for even better efficiency.