Rainbird 1408MX 2 Gpm Pressure Compensate Bubbler. The Rain Bird 1408 is a 2GPM Pressure Compensating Bubbler. This bubbler features low-flow rates that allow water to be absorbed as needed, reduced run-off, a flow that will not fluctuate at pressures between 20 and 90 PSI, no flow adjustment for increased vandal resistance, and corrosion-proof plastic and rubber construction for long-lasting durability. It comes with a 5-year professional customer satisfaction policy. This model comes with a umbrella patterned spray.