4Pcs Colorful Glass Hand Boilers, Heat Transfer and Vapor Pressure Demonstration, Spiral Glass Desktop Science Display, Office and Home Decor, 6.25 Inch

All 4 made it thru shipping to our house. They really work, and everybody I've shown them to thinks they are fascinating. I've never seen anything like these before and think it was a worthwhile purchase.

The media could not be loaded. These have entertained our kids and grandkids of all ages for years. Love the set. Very fragile works of art and science.

U just hold it and watch main thing is that it’s very fragile other then that this product is very great tbh and I like physics and things like this and like I said does exactly what it’s supposed to do like it’s shown unlike other Amazon products let’s be honest.

They work great. Kids loved them

Be careful these things will break if you sneeze on them

They are really nice and my kids loved them but man they are so breakable. The slightest things and they break

One of the hand boilers were broken when delivered but I didn't have time to order new ones for my son's birthday so I gave him the 3 that were ok. Out of the 3 only 2 worked when held. I would not buy again disappointed that only 2/4 worked.

I got these for my kiddos stockings. Everyone was passing them around even the adults thought they were pretty cool. They are made out of fragile glass so one was dropped by a six-year-old and had broken within an hour Not angry at the product. It was glass! Just know these are very, very fragile.