I don't know too much about Focus lenses. They are likely a store brand (maybe Blacks) made by other lens companies. This one is a Minolta mount I got at a thrift store along with a Minolta camera and a 50mm 1.7 Minolta lens and nice camera bag for $30 Cnd.Looks beautiful. Could you tell us about this lens? What mount? I can't find much on google because "focus" is such a common camera / lens term.