asahi pentax super takumar 1:4/300 2461053. These sell in the $75 to $125 range when used. THIS HAS A CASE. LOOKS VERY NEW. This researcher could not find any specs on this to help you make a decision to purchase, but I did find this nice review of this lens....so perhaps this will give you some information that you may need....."WOW...Outstanding Lens. There is 180 degrees of easy movement on the focus throw with smooth and easy movement of the aperture ring. The built in hood is wonderful at the end of the barrel and comes in handy as you can get a bit of flare with this lens.. The lens is built to last the nuclear winter. Big, maybe bulky to some but this is one of the reasons the Takumar lens can last 50 years and still be in perfect working condition. As to the quality of the image. With some other long distance lenses there can be some CA around the edges but it is far less than I thought it would be with this lens. With todays post processing application this can be eliminated. While I find the lens sharp it is not that unrealistic not a soft spot on the image kind of sharp. The human eye does not see as sharp as some modern digital devices can produce. What I feel Takumar did with this lens was create a sharpness that matched the human vision. Colors pop especially if they are contrasting. Colors seem to glow with this glass which can make for a wonderful shot. Being a 300mm it really does a nice job of ring the hosts closer. I often pull over to infinity focus because I am thinking about how far away th object is only to have to back the focus down. It will turn a bit past infinity which is anything over 300 feet. Less than three hundred feet and you will find yourself backing off the focus to get it clearer. I think maybe I'm just a bad judge pf distance.Read more at: https://www.pentaxforums.com/lensreviews/S-M-C-Super-Takumar-300mm-F4.html#ixzz5gO5hHx1J