The WM4PD-2-18.5-S from Werbel Microwave is a 4-Way Power Divider/Combiner that operates from 2 to 18.5 GHz. It can handle an input power of 30 W, provides more than 10 dB of isolation and has an insertion loss of less than 2 dB.
The WM4PD-2-18.5-S is available in a module that measures 3.00 x 2.00 x 0.38 inches and has stainless steel SMA female connectors.