A notice about the 'spec-plate' appeared in the 1973 Centuri catalog. Enerjet, when Irv Wait owned it, did not feature spec-plates. A quick glance of the 1972 Enerjet catalog has no reference to spec-plates even though Enerjet kits came with them.

The AeroTech kit serial number plate was the idea of Scott Pearce at AeroTech. The Enertek kits would not have included this item. As it was, the serial number plates for the AeroTech kits were kind of pricey, even in quantity. I believe they costs fifteen cents each in quantities of 2500-5000.

Bob