First Flush Washers – Black
Slow release valve set for diameters 0.25mm - 1.0mm. This is for slightly slower draining than the red, K0002 washers.
The smaller the size, the slower the water will drain - this is the perfect solution where you have a smaller first flush diversion chamber or if you want to perform first flush diversion less often.
Easy Installation

First Flush Calculator
Easily calculate how much water you need to divert and discover which First Flush Diverter is right for you.

Design Service
Improve your existing Rain Harvesting system or design a new one with the help of our experts and our free system design service.

Rain Harvesting™ Handbook
A guide that will provide you with help and inspiration to start your rainwater harvesting journey today.

Design Service
Improve your existing Rain Harvesting™ system or design a new one with the help of our experts and our free system design service.