Review on Bio Plas Assorted Polypropylene Microcentrifuge by Jason Unruh

I am a student and have used these microcentrifuge tube racks before. That's why I was looking for them. They are of good weight and very strong. It will take some effort to break one of them, and most likely it will have to be done on purpose. The description says it fits a variety of tube sizes and it can be done if you want it. However, it appears to be made for easy use of 1.5mL tubes. Anything larger will most likely not fit in the indentations, and anything smaller will be fairly loose. The 1.5mL microcentrifuge tubes will wobble slightly when placed in the rack. But it's like a test tube swaying in a test tube rack, it won't fall out and it's pretty safe. The rationale for the 4-star rating is specific to this listing. As another reviewer mentioned, there are no covers, which I was really hoping for. The description states that the covers are sold separately, which contradicts the title of the ad. Before ordering I contacted customer service to find out what it was and was told it had cases (according to their computers). It's not like this. To make up for this, Amazon offered to return the shelves or get a partial refund and keep the shelves for me. I kept the coasters because they serve their purpose fantastically. Another issue with the listing is that it says that rotating the stand to the other side will serve smaller pipes. That's not true either, the other side is a completely flat surface. Pipes can only be inserted from one side. I would highly recommend these racks, but be aware you don't get lids with them.