I was disconnected four times today.  I bought this sprinkler head and worked for two hours trying to get it to work.  then I discovered it was missing a trip pin, part 105720, (a tiny cotter pin).  I cannot order it on Rainbirds website, nor will they pick up the phone.  I have spent 4 hours now on one product, trying to get it work, looking up the problem and trying to connect with Rainbird.  Pretty outrageious really.