Amphenol RF's micro coaxial (MCX) series connectors are available with 50 Ω or 75 Ω options and have broadband capability ranging from DC to 6 GHz. In addition, the MCX series features secure, fast, and easy snap-on/snap-off coupling. MCX connectors were first introduced in the 1980s and conform to the European CECC 22220 specification.

This series provides designers with options where weight and physical space are limited. While the MCX uses identical inner contact and insulator dimensions to the SMB, the outer diameter of the plug is 0.140 inches which is 30% smaller than the SMB. A range of connectors are available, including printed circuit board and cable connectors.