A 24 hole black plastic carry tray from Thailand. Length 450mm; width 275mm; height 45mm. The hole diameter at the top is 60mm; bottom hole diameter is 50mm.
Pots/Tubes suited to this tray are as follows.
Port Tube PT060, fits well into the pot holder even though it does not sit down on the bottom of the base
Port Tube PT050, sits down onto the base of the pot holder and while a little wobbly at the top of the holder - quite acceptable.
There may be other tubes that are able to be used in this tray.