DB59BNCU F-Conn BNC male for RG59U double bubble. The DB 360 Compression Connection System creates two 360 º compression connections (one interior and one exterior) providing a permanent, double bubble connection. Ideal for security cameras and other exposed wiring installations. The unique double bubble connection provides superior protection against moisture leakage limiting poor signal quality due to the elements. All this in one complete system! Use CPLCRBC-BR crimping tool.