It would be helpful to know if these are the heavier weight bags like Ziploc brand freezer bags or the lighter weight (I’m assuming that) like the Ziploc brand so-called “storage bags” (which are nearly as light weight as there “sandwich bags”)?
I don’t think you’re gonna get more info than this:
Oddly, Ziploc brand bags use nearly identical language for both the storage bags and their freezer bags. When I compare them to bags from several packaging supply companies (who have separate catalog pages by bag weight and quite clearly state the thickness by mil (2, 3, 4, and 6 mil bags are available in about 50 different sizes). Of course they are much pricier than what has been offered on WOOT! and I am amazed some time at the information you people can pry out of Amazon and / or suppliers. I haven’t seen a “branded” (Ziploc, or others) zipper storage or freezer bag that actually gives the mils on the packaging. But Ziploc “goofed” and put the mils of the various bags on their website at one time, and screenshots of the info are still floating around, plus if you dig deep enough into the SC Johnson website you can find out the thicknesses there. Currently sandwich bags are only 1.75 mils, storage are 2.25 mils and freezer are listed at just under 3 mils (not much difference considering they charge nearly twice as much for freezer vs storage). I also had bought 4mil bags from several sources back when I was part timing a fishing lure business, and watched them triple in cost over a period of only about 8 years.