A Schron bojowy dwusektorowy (two-sector combat bunker) built according to Regelbau B1-5a specifications, located in Poland. This type of bunker was part of the fortified defensive structures constructed during the Cold War era, designed to provide protected combat positions for military personnel. The Regelbau system, originally developed by German engineers during World War II, was later adapted and utilized by various Eastern Bloc countries, including Poland, for their own defense infrastructure.
These bunkers typically featured reinforced concrete construction and were strategically positioned to support local defense networks.