Rain Bird Xerigation XP-600X: 6 inch Pop-up Device The Xeri-Pop operates at 20 to 50 psi base pressure when supplied by 1/4 inch distribution tubing For optimum performance use 40 psi or 50 psi pressure regulator Barb inlet accepts 1/4 inch distribution tubing All plastic parts in the Xeri-Pop are impact resistant. All external parts are UV resistant