BNC RF connectors are commonly used miniature quick connect/disconnect connectors. BNC connectors have a characteristic bayonet-style, twist-to-lock design that features two lugs on the female connector that engage slots in the shell of the male connector. BNC connectors are mostly used below 500 MHz for applications including video but can be used in applications up to 4 GHz. They are available in 50- and 75-Ohm impedances. BNC connectors are widely used in test equipment, surveillance video, professional video, and radio antenna connections. Specially designed 12G-SDI BNC connectors are also available to handle signals up to 12 GHz for uncompressed 4K Ultra-HD video.