I have been meaning to get one of these types of containers a while and saw these in the UK Retailer The Range for £3.99.
They had a larger version for either £5.99 or £6.99.
I wanted one mostly for the cage that Jay is in with Eve because he tends to tip the water pots up very frequently.
I checked them while in store to see if they locked and unlocked easily and they seemed to move smoothly and without issue.
I have only just popped them in the cage today so if I come across any faults I will note them in this thread.