>>1582868The plastic boxes are industrial grade Eurobox or European container standard with dimensions 600x400x170mm and more or less hold 28L of water/nutrients once you fill them so the water level touches the bottom of the 2 inch net cups.
As to their availability here in Europe is somewhat easy in the net and I guess in other parts of the world you will get equivalent standards. Just be mindful industry uses all types of boxes with/without handle holes, holes in the bottom and such. Clearly you want one without any holes at all.
I got them because they fit nicely in the plastic pallet (also part of the standard) and wanted a system that is mobile and easily expandable (although I haven't moved the setup since the start nor do I plan to expand it as I produce more lettuces that we really consume).
The water volume is plenty for 5 lettuce (I do 4) per box in a very hot summer so you could probably get even shorter boxes.
The sheets are Polystyrene and while the originals still work they do show some degradation so I would replace them with Styrofoam which is a much better material. Thickness is 2cm or so.
One final thing. The boxes and the pallet are way overkill price-wise for a simple lettuce setup but I like things to look nice and last long.
