Just purchased some "new" wear rings. They arrived and the packaging is more blue-green rather than the bright blue I'm used to seeing from Polaris. The plastic rings are also very yellowed and quite hard (won't surprise me if they break when/if I install them). The part number is correct (B10) but only Polaris 380/180/360 is listed on the bag.

Opinions please...is this really old stock? I'm concerned because I know plastic can degrade over time or during UV exposure. Also concerned that the rings are so hard, they could end up marring the plaster.