**Background:** Scientist by training, then I worked in a pharmacology lab for over 5 years, along time. I have been around labware for a significant part of my life. However now I use lab ware for my cooking chemistry. I can't help but use my scientific mind to experiment in the kitchen. And I find having beakers really handy. Being able to see clearly as you mix things into solution. Beakers pour better than a lot of other kitchen glassware less dripping in better control.**Build Quality:** This is a nice set of beakers. They are borosilica glass. the GG-17 is and has similar properties to Pyrexx borosilica. IF your not familiar the properties of glass like this is they are extremely clear extremely chemical resistant and deal with thermal shock better than typical glass. I these Yinmazzsan beakers are definitely thicker than average Beakers. They Definitely thicker but not as this as special heavy duty beakers. But well above average.The markings are really not made for measuring if you really are measuring you should be using a graduated cylinder. But just for reference, I tested and measured based on the measurement lines and are as follows500 ml Beaker 500 ml line gave me 475 mL250 ml Beaker 250 ml line gave 247 ml100 mL beaker 100 mL line gave me 96.6 mL50 mL beaker 50 ml line gave me 53.125 mL beaker 25 ml line gave me 26.1.These values are close enough as again if you're doing fine to measuring, you really should be using a graduated cylinder.These Beakers are also slightly larger than their stated size. So for example a typical 100 ml beaker can barely hold 100 ml. The Yinmazzsan beaker can easily hold 100ml maybe even 108 ml and starts spilling at about 112 mlThe one of the most important property of a beaker is the wall thickness appropriate to what you're doing. And then even more important how it pours. I really like to spout on these. It gives you a lot of control with little to no dripping. The other bonus is the three smaller sizes the 25, 50 and 100ml all fit inside each other perfectly without stressing the spouts. You can fit all five together inside each other, however the 100 spout pushes into the 250 and the 250 pushes into the 500 in a way that makes me uncomfortable for long term storage.I have a set of authentic corning Pyrex beakers. They were three times as expensive. I took a couple of side-by-side photos and clearly Yinmazzsan beakers are thicker. And the Yinmazzsan beaker of the same stated size are actually larger. So the corning Pyrex hundred mill beaker holds exactly 100 mils it's actually not practical to put 100 mils. Where as the Yinmazzsan beakers can actually comfortable hold about 8% more than their stated capacity.**Conclusions:** I think if you're a home cook who is into food chemistry or your Walter White. Bottomline this is good glassware and can comfortably recommend these for real lab setting or in a home food lab or other questionable activity setting. The key features of this glassware are their walls that are thicker than typical beakers and they are slight oversized. So in a lab if you're using 500 mil solution, you would typically pull at least a 600 ml beaker but with these you could get away with actually using a 500 ml beaker. Unless of course you're stirring aggressively.