Corning Pyrex #4980-PACK(RS), Narrow Mouth Erlenmeyer Flask Set with Rubber Stoppers, 5 Sizes - 50, 125, 250, 500, 1000ml

These are standard Pyrex quality flasks in various sizes. Nothing remarkable, just good Pyrex quality and reliability.

Good quality but the I will not be using the rubber stoppers iwith my fermentation due to their strong odor. I will replace them with cork. A good selection of sizes in the order is perfect for what I need them for.

I've always been able to trust Pyrex lab equipments and this is no exception.

Don’t even waste your time with the cheap Chinese Borosilicate. If they can send it without it getting broken(speaking directly at you Karter and Stony), it’s probably not worth spending your money on. Rippled bottoms and chipped glass constantly. Pyrex, American or German, is way better than anything else offered on Amazon. Spend more, waste less. Chinese glass is full of flaws. You can throw the box around on the floor, and these won’t break. Do better, Chinese suppliers, because you’re not even close.

I bought this set for some homebrewing stuff, so I don't really need accuracy or temperature tolerance. Overall, the set works well for mixing yeast starters, nutrients, and fining agents. My only complaint is that a couple of the stoppers I got with this set were too small for the larger flasks, and they fall right into the two larger flasks. The smaller sized flasks have correctly-sized stoppers, though.

Definitely worth the price I bought a few other flasks and had them break from thermal shock these have never had any issues.

Nice quality glass so far.

It's the all capital Pyrex logo, and they've stood up to microwaving and the dumb non-scientific stuff I use them for.

Excelente!!!