Mark - is the shiny tube on the left threaded on the interior top? Inasmuch as it is not threaded on the exterior top it will not work in a MEC reloader.
There would be no way to hold it in the press after resizing and trying to eject the full length sized hull in stage one. It needs a little more study to determine its usage. The dark steel die is as identified here earlier, I believe. It might possibly be a base resizer using a plastic mallet to drive the hull into the resizing ring and then a wood mandrel to drive the hull out before or after decapping. As you know, the old hand reloader tubes had a flare at the top, they were not straight cut. The flare was necessary to retain the tube in the hand while hitting the wood mandrel inserted into the decapped hull to eject the hull
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What is it?
Threaded Mode