I grabed the mike I bought with the Heatkit SB104 I built back in 1976. The base is 423A. The mike on top is an EV Model 638 hi-z dynamic. 73 de Richard W5SRB > I would like to find out what EV mic would have been teamed up with the stand that I have. Under > the base I find a number 423a. It has the grip bar switch with a small lock button.