I guess I'm not a manufacturing guy, but in a pile of mystery stuff I ordered off ebay, came two envelopes with these die stops in them - I'd never even heard of a die stop, and here are two new and unused ones, with instructions and everything - it's kinda interesting - I suppose something like this isn't used anymore, but I've never acutally been next to an operating progressive press (ok, what is a progressive press?)
anyway, for intellectual interest, here is the link to the auction - I think the photo is almost good enough to give the idea and show the installation diagrams - looks like an easy enough thing to make if you have a use for them
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I haven't see something using an exchange name in a telephone number for a long time - these must be pretty old