Noodler's Konrad Brush/nib Interchangeable ?

[onotopen]

Does anyone know if the Noodler's Konrad Brush 'unit' is interchangeable with the 'conventional' Konrad Section/Feed/Nib ? Putting it another way, is the barrel and piston identical for the nib and brush versions of Konrad.

 

Thanks..

[prime.lens]

Just tried this. The nib+feed will go into a brush pen and works. The reverse isn't true -- the brush won't go into a fountain Konrad since it needs threads to screw into.