Can U Identify These Aperture Plates?

[Jim Cassedy]

These two aperture plates were in a box of assorted cinema odds-&-ends that I acquired
several years ago. I know I've seen this type of plate before, but my mind is a total blank
on which type of projector they fit. I'm sure somebody here knows the answer. THANX!
DualPlate 2.jpg

[Tim Androes]

Simplex with a turret, prior to Millenium model but don't remember which exactly

[Tim Androes]

on second thought...went and looked thru the manuals for Simplex...those look very similar to the illustration for PR2000 Millenium apertures except your's have an extra small hole

[Randy Stankey]

I agree. They are for a Simplex with turret and aperture changer.

The projector has a slider that runs on a rack and pinion. The clip that holds the plate was always coming undone and the little, metal flap would fall open. I don't know how many of the projectors I used to service would always seem to have splicing tape holding the clip shut!