I was looking through Rob Cook's Publication, "The Rogers Book" - Second Edition, in the section identifying the various strainers used throughout the years.

When describing the Rogers "clockface" strainer (Swiv-O-Matic Perma-Tension Snare Strainer), it states that around 1967 the "clockface" was elongated. It also states that the letter D stamped just below the knob at the top would identify the strainer as a Dyna-Sonic strainer.

QUESTION: Did the Rogers Drum Company use any of these strainers with the stamped D on its Fullerton Powertone snare drums? I ask since I recently viewed a Powertone that was being offered with the Fullerton Tag on the interior of the shell and the stamped "D" on the clockface strainer. Would this have been a replacement strainer (I imagine that they'd be interchangeable), installed by the current owner or could it have come from the factory in that configuration?

As usual, THANKS in advance for your input!