4 in. 1800 Series pop-up spray head Compatible with all female threaded spray or rotary nozzles (Sold Separately) Strong stainless steel spring provides reliable stem retraction Constructed of time-proven UV-resistant plastic and corrosion resistant stainless steel parts, assuring long product life Installed in parks and backyards across the globe, Rain Birds 1800 Series is the #1 commercial-grade irrigation spray head brand in the world. Chosen for its reliability, heavy-duty materials and versatility, the 1800 Series has first-rate quality built in for reliable operation and long life. Their superior components and features make them the spray heads of choice for a wide variety of applications. Additional features: Exclusive co-molded wiper seal features an encased plastic "cage" to provide unmatched resistance to grit, pressure and the environment. Pressure-activated, multi-function seal design assures a positive seal without excess "flow-by which enables more heads to be installed on the same valve. Precision controlled flush at pop-down clears debris from unit, assuring positive stem retraction in all soil types. Two-piece ratchet mechanism on all models allows easy nozzle pattern alignment without tools and provides added durability. Pre-installed orange 1800 Pop-Top flush plug blocks debris from entering after flushing. Allows for easy nozzle installation. All sprinkler components are removable from the top without special tools, providing for quick and easy flushing and maintenance of the sprinkler. The 1800 Series accepts all Rain Bird spray nozzles. Flow-by: 0 gpm at 8 psi (0.6 bar) or greater;  0.10 gpm (0.02 m³/h; 0.36 l/m) otherwise Operating Range Spacing:  2.5 to 24 feet (0.8 to 7.3m)* Pressure:  15 to 70 psi (1.0 to 4.8 bar) Dimensions ½" (15/21) NPT female threaded inlet Model and height: 1804, 1804CA: 6" (15.2 cm) body height; 4" pop-up height (10.2 cm) Exposed  surface diameter: 2¼ " (5.7 cm)  Downloads 1800 Series Spray Heads Brochure 1800 Series Spray Heads Tech Spec Spray Head Adjustment Instructions and Troubleshooting Guide