Thanks! Would you know how these Biogons are versioned, meaning, how to find an old one?
There are only 2 1/2 versions of the Hasselblad/Zeiss 38mm Biogon.
It was introduced in the Hasselblad SWA in 1954.
In 1973 the T* multicoating was added, however the optical formula remained the same.
That lens remained unchanged until 2001 when the 903SWC production ended.
In 2001 the lens needed to be redesigned, as some of the glass contained lead and arsenic. No go by the new environmental standards! The camera with the new lens became 905SWC, easily recognizable at its CFi style. It was produced until 2006.
There was a lot of debate back in the day whether the 905 was inferior or not to the 903. It's really splitting hair in my opinion.
Note that the lead/arsenic issue was a problem to the workers and the environment, not the users of the SWC! Don't hesitate to buy one and use it, it's a wonderful camera. As Sirius puts it, an SWC will be detrimental to your financial well-being (a 905SWC even more so), but definitely not to your health