Fender EVH 5150 III 50W Stealth EL34 Standard Retube Kit

These amps are adjustable and you can use the factory test points and a Multimeter or you can use a bias probe with a Multimeter which is more accurate, or you can use our All-in-one "Pro One" bias probe which reads the plate voltage and the plate current simultaneously. 

You can use our Generic Bias Video for reference.

The video below explains the difference between bias probe types.