Edit
The 9M111 Fagot (Russian: Фагот; "bassoon"; NATO reporting name AT-4 Spigot) is a second-generation tube-launched semi-automatic command to line of sight (SACLOS) wire-guided anti-tank missile of the Soviet Union for use from ground or vehicle mounts. The 9K111 Fagot missile system was developed by the Tula KBP Design Bureau for Instrument Building.
The missile is stored and carried in a container/launch tube. It is fired from a 9P135 launcher post, a simple tripod. A 9S451 guidance box is fitted to the tripod with the missile sitting just above. The 9Sh119 sight is fitted to the left side (from the gunner's point of view). The complete launcher system weighs 22.5 kg (50 lb). The gunner lies prone while firing.
North Korea was said to have acquired a number of the systems during the late 1980s until the 2000s. These were subsequently reverse-engineered under the designation Bulsae-2. It was advertised under designation AT-4MLB by North Korean proxy company GLOCOM, in brochure it was stated that it is controlled by laser beam guidance method, which was an upgrade designated Bulsae-3. Its use was first reported in 2014 in the ranks of the Izz ad-Din al-Qassam Brigades and the Al-Nasser Salah al-Deen Brigades.
1