Nikkor-T 10.5cm f4, commonly known as the Mountain Nikkor, was introduced in 1960. It is one of the last lenses designed for the Nikon S series. It has a 3-group, 3-element construction and a filter diameter of 34.5mm. Even for its time, f4 is considered a relatively slow lens, but this contributes to its lightweight and compact design, which is a significant advantage. Indeed, it is sufficiently effective for outdoor photography. The lens weighs just 255g, about half the weight of the Nikkor 105mm f2.5 for the same Nikon S series. While it isn't as compact as Leitz's Mountain Elmar, it is small enough to fit in the corner of a camera bag, making it an excellent lens for travel and hiking. It is somewhat rare. There are no noticeable scratches, and it has a very clean appearance with little sign of use. The movement of the helicoid feels slightly heavy, but it does not affect practical use (maintenance is also available at an additional cost). The aperture blades are clean. The lens has been checked for focus and rangefinder coupling using a Nikon S body for inspection. There is a slight presence of dust inside the lens, but there are no significant scratches or haze, resulting in clear and unobstructed glass. It comes with the original hood, front and rear caps, and a UV filter. An excellent addition to any collection.