Mil-i-28791; vswr 1.25 to 1 max; insertion loss 0.4 db max; isolation 20 db min; impedance 50 ohms; rf power input 1 watt; 2 female connectors,mil-c-29012; nickel plate qq-n-290 class 2; four 0.156 in. Dia holes in each corner; circulator with 1 port terminated