ULAB Test Tubes with Black Screw Caps, Vol.30ml, Dia.20x150mm with Marking Area, Test Tubes Shot Glasses, Borosilicate Glass Material, Pack of 12, UTT1014

The item arrived on time and in great condition. The tubes are perfect for running water quality tests on my aquaria. They are very sturdy, actually dropped 3 once and they survived the 2 foot fall. I will definitely buy more when needed.

My first order was in early 2021; the items appear identical across this one year time frame.The product appears to be as advertised. Based on a visual inspection of the glass it appears to be reasonably thick borosilicate glass.My use case is storing premeasured doses of aquarium dechlorinator in ambient household temperatures. It works well for this purpose and the cap seems sealed enough to prevent evaporation.

I use these to store beer yeast and these 25ml tubes with screw cap are just about perfect for this. I just ordered some more. The yeast stays good for a long time. The caps are airtight and do not leak any of the fluid. I use a sharpie to write on the glass what the contents are and the date of storage. After I use the yeast I clean and sanitize the tube and cap, clean the marker off with alcohol and I can reuse.

These were packed well and none broke. The flat bottoms are nice for my intended use.

They came without any cracks and was nicely packaged. They can store a bit more than 30 ml. In the picture, both of the tubes have 30 ml water in them. Even with vigorous shaking, there is no leakage. All of them stood by themselves without wobbling. When screwing on and off the caps, it didn't feel like it would break from the force. All in all, extremely satisfied.

I liked the sample tubes but three of them had cracks in the glass where the caps screw on.

I use them mostly for collecting sand and dirt during my road trips and then do the trick. They are suitable for liquids as well as they seal quite well. Overall, a high quality product, and would definitely buy again.

I bought these tubes to hold powdered, crushed pill medication. The glass tubes are smooth and perfect and the lids are the best - easy to use, they provide an excellent seal.

For school laboratory use in teaching

quite handy to have as I use mine for water testing purposes...