The Pentax K1000 (originally marked the Asahi Pentax K1000) is an interchangeable lens, 35mm Single Lens Reflex (SLR) camera, manufactured by Asahi Optical .from 1976 to 1997, originally in Japan. The K1000's extraordinary longevity makes it a historically significant camera. The K1000's inexpensive simplicity was a great virtue and earned it unrivaled popularity as a basic but sturdy workhorse. The Pentax K1000 eventually sold over three million units.
This camera definitely has some wear on it so make sure you look at the photos before you buy. It is in perfect working condition, there is just some heavy wear on the outside frame.
The serial number on the lens is: 4455041