The 4x4 Hybrid is a matrix of Hybrid Couplers arranged so that signals applied to any of the four inputs will be split equally between the four outputs. This allows combining of multiple signals in the same wireless band to a common feeder cable, as might be required in a neutral host in-building distributed antenna system. Unused output ports must be terminated externally in 50O, with an appropriate PIM performance. Note that the phase relationship of the outputs in this model is not consistent. The CM-88KE is designed for harsh ourtdoor applications in corrosive salt fog environments. It has 4.3-10 female terminations and a PIM rating of -161dBc.