Plus, Rain Bird does not reveal their precipitation and GPM for anything higher than 30 psi. A side note, Rain Bird 1800 PRS heads do not adjust pressure to 30 psi. Had a site where incoming ptessure was 66 psi. Rain Bird heads only pressure regulated to 42 psi. Checked what would happen with Hunter 30 psi heads,and Toro pressure reg 570zpr. Hunter and Toro reduced pressure to exactly 30 psi. Checked another site that was 115 psi. Rain Bird reduced pressure to 48 psi, while Toro and Hunter reduced pressure to exactly 30. Lost of misting at 40 and 48 psi.