30 Pack Sterile Plastic Petri Dishes with Lid

They are plastic disks...

As expected.

Great petri dishes that did the job well. Ultimately I could have ordered from a scientific supplier for a little cheaper but the convenience can't be beat.I don't know what the claims regarding sterility on these pertri dishes are but I have never had any issues with contamination or growth after pouring agar. I also haven't done any additional sterilization or cleaning prior to use. One issue that I do have with the dishes is that some of them seem to get stuck together. They are easily separated but sometimes as I'm reaching for the next dish in the stack a second one will come with it and then fall during the transfer. Easily solved by just taking a little more care to ensure that there are no extra lids or dishes attached.

bought them for a party, they're really cute but i had to throw a good number of them away before using them because they were cracked :(

This material is weak and brittle. Six of my plates showed up already broken.

Beware the heavy handed user, these are flimsy and therefore easily breakable. Also, 2 were cracked before I opened the box and one with a chunk taken off the corner of it's bottom tray.

Strike one against this product: It is a lie to proclaim and sell these dishes as "Sterile". This statement can be easily corroborated by anyone who has access to these dishes and simply uses them as advertised. They may have been sterile the moment they rolled hot off the production line but they do not stay that way through handling, packaging, storage, and transportation. The fact is, what is being advertised here is demonstrably untrue and if a customer were to move forward in good faith with these claims, these dishes would absolutely botch any work they intend to accomplish (Buyer Beware).Strike two against this product: Due to the type of plastic used to make these dishes, they are seemingly impossible to safely sterilize or even pasteurize without destroying the plastic (see photo results of my 8 dishes post steam bath attempt) true polystyrene plastic shouldn't melt until it gets to 240c or 464f which leaves me questioning whether or not this is pure polystyrene plastic or if there is something else in the mix that is potentially lowing this product's melting point?You might be able to get these dishes sterile with a UV sterilizer but if you have that kind of money you can afford better dishes to begin with.In the meantime, my remaining dishes will be allocated to the one thing they are still actually good for; kindergarten art projects.TLDR: Buying these dishes is the lab equivalent of buying an aluminum impact driver bit. You might think you are saving money with this cheaper option when in reality you are spending slightly less money on something for the privilege of throwing that something in the trash. Save your money by spending a little more on better quality dishes that can actually endure their intended use.

A few were broken. Shipping package was fine. Not reliable.