O/a 3.8 in. Lg; oper pwr rqmt dc 17 to 29v; m54 to p125 degrees c; 200 to 300 hz audio range; cont sig dy cycle; 4 hz porm 10 pct to 6 hz porm 10 pct interruption rate; hermetically sealed; 1 connector receptacle type terminal military p/n ms3106a16s1p; hole mtd type 4 0.173 in. Diameter mtg holes on 1.921 by 2.125 in. Mtg ctr