APITech's high-reliability BOM10648 cavity filter is designed to solve the emerging 5G C-band interference issue with radar altimeters and other critical avionics systems operating in the globally allocated 4.2-4.4 GHz aeronautical band. The passband of 4.2-4.4 GHz has less than 1 dB insertion loss and greater than 50 dB of signal rejection outside the aeronautical bandwidth with propagation delays of less than 2ns. This filter housing is 4 inches long and 1-inch square with connector and mounting options available to satisfy any installation requirement.