Ruby Bias Probe

This works well for 50w style amps ( 2 output tubes ). It comes with RCA style connectors so if you have testers like mine that require 4mm Banana plugs, these will not work, without modification or a RCA to 4mm Flex Pin adapter. Once you're properly connected, it works wonders for setting push/pull biases, like those found on Blackstar HT Club 50MkII amps. Its build quality is not quite as good as my bias probes from Euro Tubes, but the accuracy is as good and thats all that matters. It does what its supposed to do.

nothing to say its a nice product