PCB's (Pressure Compensated Buttons)
PCB’s limit how much water goes to unregulated drippers (drippers with no set flow rate). If using an Angled Drip Stake or Blue Fast Flow Drip Stake in a DIY system with a high-pressure pump (like the Professional AQ7000 25mm Pump), they’re a must! Fix the PCB to your dripper with a small section of delivery pipe.
Note: PCBs will not work with smaller pumps than the AQ7000 as they do not create enough pressure.