said by iknow:
that's "low flow" per head. i came across info on something similar, and all the heads could be operated at once!., that was a selling point they made.
IIRC, my low flow heads are 1.5 gpm, and AFAIK are required in this area, even though currently there is plenty of water to go around. I'm used to this flow rate now, but as I said, that one in Chicago was really nice!