Hagen Cat-it covered large pan/litter tray with door

I am very interested in purchasing this product but I don't think my cats will be able to cope with the door. (One still hasn't figured out the catflap.) Is it possible to remove the door? or is there a similar product without a door?

Yes it is, although the door does work like a cat flap so they may get used to it. Also just to let you know the one we currently have in stock is purple and blue rather than white and blue