Fits for models:
GF-8585, GF-8686, GF-9595
RT-10, RT-20, RT-1122, RT-1155, RT-1157, RT-1157H, RT-3151
RT-1616 Optonica, RT-3838 Optonica
and some other models, of course......
You should be sure that this is EXACTLY what You need. :)
Self-made, not original part. Tested.
The object of offer are only idler tire, take-up rubber and intermediate gear. Not mechanism.