The different model numbers mainly have to do with whichever retailer is selling the LitterMaid and what items are included in the sale. The very early models had two large plastic screws inside the litter pan. The labeling on top of the unit says "LitterMaid" in black letters. The sides of the box are smooth, with no latches. This is the LM-1 model.
The units were sold for a time in Europe. The model numbers were LM100E and LM300E. While never having seen them, I would assume that the 100E is the standard size unit and the 300E is the same as the Mega except that these units came with an AC adapter that would work in Europe.
As of this writing, the newest LitterMaid models are the LME (Elite) series. The LME 5000 series is the smaller or standard size and the LME9000 is the larger or Mega size. The LME9250 is the same thing as the LME9000 except that the 9250 includes a "Kabana" cover that fits onto the top of the unit. The LME5500 is the same as the LME5000 except that the Kabana comes with the 5500. The LME (or Elite) models are a complete re-design but the waste containers and ramps will still fit on all models. The LMT100 tent will not fit on the LME Elite units. The Elite series LitterMaids come with a small ozone device to cut down on odor, a timer switch so that you can shut it down at night if the noise bothers you and the rake is now stainless steel instead of nylon. The rake is easier to remove for cleaning. Personally, I would not use the timer if it is not absolutely necessary. Cat deposits may build up and stick to the pan which would cause strain on the gears inside the motor/rake arm when the timer kicks in. The timer is also a clock so I guess you or your cat can use this to check the time. Now you will have one more clock to change when the power goes out and comes back on. ;-)
The LME9000 Elite Mega
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