These are great jars. I got the 122 oz and followed up with a purchase of the 1.2 gallon / 37 oz combo after I examined and approved of the 122 oz. I use them for five pound bags of protein. Vanilla, chocolate, and unflavored, along with some superfood green powder.This is thin borosilicate glass. It feels delicate. But borosilicate glass is quite sturdy. I have not dropped these jars or done anything to test their durability (other than the hot saniti-rinse cycle in the dishwasher). But, I have borosilicate glass drinking glasses that feel very delicate. But, I’ve dropped them on a linoleum type floor from counter height and knocked them over on a quarts countertop. They just bounce around with no breakage (usually—I’ve done it more than once and they’ve broken after hitting the countertop from a couple of feet). It’s what I love about borosilicate glass. Very thin and very strong.These jars are made out of a thicker version than my drinking glasses. But, they still quite thin and no doubt quite sturdy.The glass clarity is crystal clear. There is no lip on the jar. So, they are easy to polish up between fills.The bamboo lids are not precision cut. But you can’t tell unless you open the lid and examine it. They look beautiful on the counters.I’ve purchase 8 or 10 different glass jar types. These will be my go to jars when the need for a jar arises. They are crystal clear, easy to clean, delicate in appearance, and very probably very difficult to break unless you drop them on stone. But, most glass will break if you drop it on stone.