I have the JMI NGF SCT mounting rings for the larger 3" visual back threads (ADPT3SCT)avaliable for sale. The item is brand new and has not been used before.
Larger SCTs include an adapter to reduce the 3" diameter threads down to the standard 2" size but this adapter has the benefit of being non-vignetting (no obstruction of the light cone).
Asking for $25 + $5 shipping
Doing Spring cleaning for unused stuffs.
Paypal or money order accepted.