In "D-L-1" series, the male and female fit in the same hole cut-out and are front or rear mountable. The Neutrik NC4FD-L-1 is a universal D-size metal body XLR panel mount with 4 female connectors, rear solder cup terminals, Nickel housing, and silver contacts. It is RF protected via a 3-point coaxial ground contact shell of the mated connector.