The quality of your communications will never be better than the quality of your coax.  FireStik's dual lead, co-phase harness assemblies are made from their RG-59A/U, Fire-Flex coaxial cable.  They may be used on any dual antenna installation.  Check out these features:

• Stranded center conductor to maximize flexibility and prevent untimely breakage. 
• Shielding coverage that averages 95% to protect against RF leaks and interference. 
• Polyvinyl center insulation for ruggedness and longevity. 
• Performance that exceeds mil-spec requirements for 75 ohm RG-59A/U coax. 

    The K-9A co-phase harness is made with two 18' (5.5m) leads. All three ends of this cable assembly is terminated with PL-259 type connectors. This cable is designed to be used with K-4A or R-4A antenna studs and any mounts that use either of these SO-239 stud mounts.