FoldTier 6 Pcs Borosilicate Glass Tubes, 12mm Od 2mm, 4 Inch, Clear | Thick Glass Blowing Tubes, Glass Pipes with Cleaning Brush, for Lab Oil Burner

Great product that handles heat very well!

Superior thermal shock resistance. This borosilicate glass tube is a critical component in my high-temperature chemical processing manifold. It exhibits remarkable thermal stability under rapid temperature cycling, maintaining structural integrity without stress fracturing. The optical clarity remains pristine even after repeated exposure to harsh reagents. Precisely dimensioned and exceptionally durable.

Perfect for what I needed. Heat resistance n still safe after multiple experiments

I ordered a 5-pack of clear 4 inch glass tubes and was very happy with the product. The price was excellent for the value. They are thick, durable, and good quality. The cleaning brush/tool that was included is not very strong/long/affective, but it was a nice touch and would be excellent if it was made for the length and width of the tubes I was purchasing.

use this product for inhalation with rhymes with wack. with a bit of brillo whis tube always works great. easy to scrape residue and inhale again. prepare for the ringing in your ears

They do not break easily and none were broken when they came in. They were a little thin but it hasn't been a problem for me. Don't let the black spots build up because it will cause cracks and catch fire while you are using them.

To short for cocktail straws. Rust in dishwasher.

Thick enough to take heavy heat. Come packaged very well in cardboard. No complaints from me.