This item is an Olympus OM System H.Zuiko Auto-W 28mm f/3.5 prime MF WA lens.  I'm not sure what's up with this lens.  The aperture ring fitted at the outer end of the lens is not connected.  So there is no aperture control.  I think the trim ring is missing.  The focus is smooth.  The glass is clean and clear.  The aperture seems to function properly when you manipulate it from the mount end.  It looks good cosmetically.  There's a little brassing on the aperture ring.  So if you can fix it you will have a nice lens.  Selling this AS IS and described the best I can.