The matching insert is an aerator/jet regulator with M22x1 thread. The matching spare part number is 606401.000.001. Unfortunately, we do not currently offer this in our range.
To convert 3/8 inches into millimetres, you can use the following conversion:
1 inch equals approximately 25.4 millimetres.
So, to calculate 3/8 inches in millimetres :
\frac{3}{8} \times 25.4 \approx 9.525 \text{ mm} \]
So 3/8 inches is approximately 9.525 mm.