Vacuum seal

The commercial material the markets use is similar to Saran Wrap like we use in our homes. However in wide use nowadays the wrapping machine they use also adds a small amount of a gas which actually causes the meat to “bloom” meaning it turns red for the days until the best sold date. After that the meat will start to turn brown.

Just two more points while we are on this subject since you said you are a newbie…the Food Saver material is “solid” and therefore it can extract the air by creating a vacuum. In that condition the meat or contents can be frozen without fear of freezer burn.

And the other topic is the UMAi Dry® bag is unlike the Food Saver material in that it breathes allowing the moisture in the meat cells to be released during the aging.
Ron