50 000 Dong An Phuoc Prison

An Phuoc Prison, located in Binh Duong Province, is one of Vietnam's larger detention facilities operating under the Ministry of Public Security. Internal prison scrip of this type circulated within the camp's canteen system, allowing inmates to purchase approved goods without handling state currency — a practice common across Vietnamese correctional facilities by the late 1990s. The K-4 designation identifies a specific sub-camp within the complex.

These notes rarely left the facility, and surviving examples typically did so through release or transfer of inmates. No central catalog authority has systematically documented the full range of denominations issued across Vietnam's prison camp scrip system.