Hoth stormtrooper question?

OK as i was shuffling through the snowtroopers i was looking at them while cleaning.
One stood out as it felt different, it felt possibly slightly heavier if not just more solid.
It seems to be made from a denser material?

The lines are much more defined and it has its COO removed. The only variation i could find is YPS but i dont know what that means?

Heres some comparison pics -odd one on the left and standard on the right - and a close up of the coo scar.
(and i am aware the skirt on the standard is a repro, actually its a good shot to show the difference)

I have no idea which lot these came from and no one has mentioned anything but he is different.







So any one know what he is? Background?

cheers

"It seems to be made from a denser material?" yep often called the hard torso version(s) and yes the detail is more defined. YPS is a german comic ? That particular stormy had a different gun ( from action force) & his skirt/cape had round holes not slits. The 'scar' on his leg has a dozen or more 'variations' from single to double scar and lots of others as well.

thanks james,, yeah hard torso version cool. The other yps one make sense, sometimes i come accross a term which is known by all but i have to ask the obvious.
And the hard torso are as common as the normal ones?

Cheers

steve