Drip irrigation tip

This is a drip tip for irrigation, adjustment of water flow is made with a tapping screw. Adjustable from few drops to many literl/hour.
It fits 4mm inner diameter tubes, very tightly to avoid popping out with pressure. It helps a light heating with a lighter to soften the tube, exprecially older ones hardened by sun heat.
A 3mm tapping screw (preferably stainless steel as it doesn't rust) is just screwed in the center hole to adjust water flow. Use pointy screws as the point will get in the