The cat using the facility breaks an electronic beam upon entering. Five minutes after he leaves, the box cleans itself by pushing clumps of used litter over the top into a plastic bag in an attached compartment. Sign of problems Cats are more likely to urinate than to defecate outside the box, and this can be a sign of urinary tract problems. Disease of the large intestine can be the cause of defecation outside the box. If your cat exhibits these behaviors, have her checked for medical problems first, to rule them out.
Most cats seem to prefer open boxes.
They like to see who or what may be sneaking up on them. The open box can be kept in kitchen cupboard or closet, giving the cat a little privacy and keeping the dogs from chomping on kitty hors d'oeuvres. An extra box should be provided for each additional cat. If you don't want to have multiple boxes, try one huge box, about two by three feet, like the kind used to mix concrete. Stay away from rubberized dishpan that sway under a cat's weight.