The Konica 4/58-400mm is an extremly rare early zoom lens for the Konica AR system (mid-1960s). There's not much information available, but a sample of the lens was sold on e-bay Japan in 2016 for about USD 750.--. Its weight is about 4.3 kg, and it is a [14/9] construction.

The image below is NOT from me. Usually I do not post a "stolen" image on my website, but this is an exception - due to the rarity of the lens I chose to keep the image and re-publish it here. I anyne knows the original copyrigh holder, please inform me!