Great gear comparison site

Maybe you all already know about it, but it was a pleasant surprise for me... I was shopping for a new sleeping mat and having a difficult time finding weight stats in one place when I stumbled upon Ultralight Outdoor Gear. I'm not sure that it will ever be the right place to buy (since it's in the UK), but it's a wonderful stat comparison site as they list the products from lightest to heaviest. Here is their sleeping mats page:
UOG - Sleeping mats

And an ounce = 28.35 grams, to answer the first question you have by clicking the link.

and a pint of beer is 16 oz 😃.

grams to ounces, ounces to pounds, and a pound is a beer!

and it won't weigh a pound for long...

Makes perfect sense to me!