I've read this thread with great interest as I just purchased a couple of older Toyo 4x5 film holders and have been looking at buying a few more. The ones I bought are older than the ones discussed here. The dark slides that cover the film are plastic, but the handles are metal. Instead of the large print "Toyo", they have the stylized S (for Sakai) in the middle, near the top. I did a light check in a dark room, using my iPhone flashlight on full power and don't see anything coming through. Does anyone know if these older holders were OK? Thanks. Click image for larger version. 

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