It is a random traveling, in the pool, cleaning unit.
It can either be driven by water flow without a booster pump, or by pressure, which would require an additional booster pump. This will be plumbed so that its intake comes off of the main pumps return line and then a dedicated discharge line to feed the in pool cleaning head.
There are different types designated by a 3 digit model number. x80 = needing a booster pump and x60 - no need of booster pump. These work off of the return lines coming back to pool from main pump. All of the in the pool return fittings will need to be dramatically reduced down except for one (1) where you feed the unit from.
Then there are suction style that plug into a skimmer or dedicated suction port. These will bring debris directly into the pump hair & lint pot basket and the finer stuff into the filter. Where the Pressure style cleaners have their own catch bag.
Another cool thing is they are equipped with a "Back Up Valve" this little doohickey will pick up the unit every 4-6 minutes and get out of any stuck predicament, like steps, ladders, corners, etc. and send it back on its way in a different part of the pool, pretty cool huh?
Good luck
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