What Type Of Mounts Are These?

I buy a lot of box lots and see these type of mounts too frequently. What are they called?
I absolutely hate them.
Thanks in advance!
Harry





*** Moved by Staff to a more appropriate forum. ***

I believe they are Showguard PM mounts.

Here is a link to an earlier discussion on these mounts.
https://goscf.com/t/41687

Bad ones.

Those are Protective Mounts, or PM for short. Very big in the postwar era from mid 1940's to around the mid sixties when Showgard and Hawid came to dominate, I doubt they were even made past 1970. They were simply awful. If you followed the instructions on the envelope they came in, your stamps would be entombed in them forever. There was a plastic tab at the top, the instructions said to use the tab to help insert the stamp into the pocket then remove the backing to expose the sticky adhesive and fold the tap down to seal the stamp in, then use the remaining adhesive backing to affix it to the page. I used them very early in my collecting and soon figured that if I just sniped off the tab after the stamp was in there I could still retrieve the stamp with tongs from the mount. Most users never did it that way.

I was offered a nice collection of British George VI material awhile ago, nice stuff, better sets. All sealed in these abominations. I passed, no way to get them out without ruining the stamp.

Actually the stamps can be removed, but it is work. It is possible to turn the stamp over and slip a tongs under one of the folded over sides and then slit the mount to remove the stamp. I have removed many stamps this way, but it is time consuming and great care is needed. But it does work.

Almost as bad as Crystal Mounts *shudder*

I have just broken down 3 pages of Poland in similar mounts.
using the same method, however I have a surgeon's scalpel
which made it very much easier.
I found the tongs (I have pointies) were not sharp enough, and grabbed the polypropylene.

Here is a typical "victim" of a PM mount. I'm really surprised that the stamp in the original posting hasn't been damaged.

Thank you everyone for your responses!
Harry