RCA 12AX7 "Blackplate"

White paint "Ariel Narrow" RCA logo.
Trapezoidal getter support

One-piece plate construction, folded and crimped.  Plates are vented by a wide cutout at the top and bottom of the center of the outer plate segments.  Plates halves facing the center of the tube are not vented.  Note single crimp on each flange.Note that the convex sides of the oval stampings on the flange tabs all face outward toward the glass.  On most RCA tubes, these stampings face alternately in and out.