Originally posted by photolady I'll call KEH tomorrow to verify it's not M42. Even so, I think it would worth having for the price and I can buy an adapter for it if it is M42.
As I said, it's listed under Manual Focus lenses/converters. KEH has a separate listing for screwmount/M42 lenses.
I'll let you know tomorrow what KEH said.
Photolady, it may be that they are selling the macro lens only. No 85-210 zoom, just the "attachment lens" = "close up filter". In that case you need to have a camera lens that takes 58mm filters to be able to use it. No m42 adapter will help.
The DA55-300 for example has 58mm filter threads if I remember correctly, and it could work well on such a lens to decrease the close focus distance and give you better macro capacity.
About the (K) SMC Pentax 85-210mm f4.5 (aka SMC Takumar...). It had a close focus distance of 3.5m (!) which is why it was sold with this "attachment lens", which was just a good quality (SMC) close up filter. It was replaced by the SMC Pentax-M 80-200mm f4.5 which was both smaller and had its close focus minima distance reduced to 1.6m.
I believe the "attachment lens" was marked exactly like the text in the add, and when people try to sell camera gear without knowing what it is it often happens that they just copy what is written on it. I may be wrong, but check this first. It would be sort of dissapointing if you expect an 85-210mm zoom and get a single close up filter.