Frankenfinder Diopter

[uhoh7]

The WATE viewfinder "frankenfinder" has exterior threads.

Could anyone tell me which diopter works and even better a US source?

I need a minus 3

TY so much,
Charlie

 

[Luke_Miller]

I believe the diopters for the Leica R8 & R9 SLRs work on the WATE finder