They are made out of plastic.
The largest tote zip lock bag available at most stores are the XXL size bags. The largest zip lock big bag available at most stores is also XXL bags.
Zip lock bags are usually rectangular in shape as they are often used for transporting files and paperwork. They have a zip fastening along the upper edge which can then be sealed to ensure the contents are not interfered with.
Only if you put holes in them. (There are, I believe, some varieties of zip-lock bags that are "breathable", i.e. slightly porous, but the standard garden variety one is not supposed to be.)
Cellophone candy bags can be found at your nearest grocery store. The zip lock bags are plentiful and most likely rivals the cellophane bags found in store accessory shops located in industrial parks. The zip lock bags are not cellophane but serve the purpose of housing the candy and some of these bags have a white labeling embedding for a easy recognition of what is contained.
cyrus
You can check the Glad website for coupons on Glad trash bags, and Glad zip lock bags. You can also check your local grocery store, sometimes they just run discounts.
They stay better in the refrigerator.
Zip-lock bags can be cheaply bought by the hundreds at your local grocery or dollar store. If you need a truly massive number of them it is also possible to order them in bulk through internet suppliers.
Jiffy Bags offers zip-lock type of plastic baggies that can be used to store various fruits and sandwiches in, and even some bags that can store larger items.
At Ziploc they have alot of different zip lock bags for freezer, fridge, pantry, on-the-go, microwave, oven and also non-food storage like; compact, multipurpose, heavy-duty and oversize.
You should use zip lock bags or sealable containers for storing foods.