I built a rack awhile back based on Cambro dimensions. The intent was for neonate GTP's. Unfortunately life changes have left me without the need.

I didn't use the lids but the polycarbonate material the tubs are made from is very durable. Like you said it can be dropped without shattering. It's also Food safe meaning it doesn't absorb any nasties like PVCX or polypropylene (sterlite tubs). As such it's great for our little friends and easy to clean.

Also dishwasher safe if they are small enough to fit.

It's also very clear meaning you can back light or if you use the lids top light and be able to see the animal.

They are rather expensive but are well worth the cost IMO.
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Jeremy Payne