Heathrow Scientific HS29022G Interlocking 4 Way Tube Rack, Polypropylene, Assorted Colors (Blue, Green, Pink, Yellow, Orange), Pack of 5

Why did you pick this product vs others?:My students use these all the time for our research. The racks are versatile, which is excellent when an experiment calls for conical and microcentrifuge tubes. Highly recommend and may buy some more.

Whether is 500ul, 1.5ml, 15ml or 50ml tubes, this classic and nostalgic tube racks will easily have you covered. It is the most overused tube rack in my laboratory and I have a lot of these. It seems that no matter how many of these we have, they almost always all get used up during the entire working day of experiments.Each side of the tube rack has different-size holes to account for your specific needs in sample preparations. I have overused these tubes during my PhD and continue to use them afterwards and it really captures the nostalgic feel while also being very helpful.It can be use for O-ring tubes in the side that holds 1.5ml eppendorf (or any 1.5ml) tubes. I have used these for western blot where it holds the O-ring prestained ladders from Biorad and works perfectly alongside my samples. I have also used it for cryogenic vials with O-ring tubes (although for cryogenics vials, I would maybe use another type of rack since those O-ring screw caps comes in a variety of volumes and some may exceed the classic 1.5ml volume). Depending on the cryogenic vial that you have, it may or may not fall right through. In my case, it tends to hold in place but test it out first before going to place it on this rack.Finally, one small rant that I have for this tube rack (but not enough to lower its star rating since I am used to it) is that whenever you are using 15ml tubes, have in mind that its lower bottom will fall right through the section of 50ml tubes. Since the hole of 50ml tubes is much larger than the 15ml, the bottom tip of the tube it will easily fall through slightly BUT it will stay in place due to its screw cap. Trust me, it will stay in place but it will wobble a lot when moving the test tubes. It is slightly annoying when you have a lot of samples in 15ml tubes and you need to be very careful for any type of sudden motion (such as a cell sediment pellet in the cell supernatant).You can also freeze your sample at -80℃ with these test tubes (as shown in the attached image).

Great colors. They didn't fit well together.

Versatile, value with color coded, bench space saving

as advertised. These do a good job especially for holding microcentrifuge tubes. Not so good for 15 or 50 ml tubes, but they will work in a pinch.

Priced right for what one receives. Not the best syringe holder, but the bet one for the $$$$.

Decent tube racks for my classroom that hold various sizes of tubes. It makes storage so much easier with little space available.

Bought these from Amazon because they were cheaper than at my university's lab supplies vendor. The product is sturdy and the holes for fitting various tubes are well formed. Falcon 50 ml, 15 ml tubes fit well. So do the standard microcentrifuge tubes (0.5, 1.5, 2 ml). I tried assembling the individual racks into larger units, and this is where the racks fail. Only two of the 5 pack could fit with each other. All others had sliding locks that were off by 1 - 2 mm and thus, would not fit with other racks. This is for both orientations of assembly (lengthwise and breadthwise). However, assembly of the racks into larger units is not a required feature for me, and I will use the individual units as such (which are good for use in a bio lab). I wanted to mention the ill-fitting racks just in case someone buys these racks for that feature.