PK machine guns that feature a Warsaw Pact side-rail bracket on the left side of the receiver can mount various aiming optics. The standard Russian side rail mounted optical sight was the 4×26 1P29 Universal sight for small arms, an aiming optic similar to the British SUIT and SUSAT and Canadian C79 optical sights. When mounted, the 1P29 sight is positioned centered above the receiver at a height that allows the use of the iron sights. It weighs 0.8 kg, offers 4× magnification with a field of view of 8° and 35 mm eye relief. The 1P29 is issued with a canvas pouch, a lens cleaning cloth, combination tool, two rubber eyecups, two eyecup clamps and three different bullet drop compensation (BDC) cams for the AK-74, RPK-74 and PK machine gun. The 1P29 is intended for quickly engaging point and area targets at various ranges. On the right side of the field of view a stadiametric rangefinder is incorporated that can be used to determine the distance from a tall object from . The reticle is an inverted aiming post in the top half of the field of view and is tritium-illuminated for low-light condition aiming. A later designed similar optical sight suitable for the PK machine gun series is the 4×24 1Р77