You don't have to solder it. Strip the rubber casing off and do the same to the other ends of both wires. Cut them even or you have one side linger than the other. Slip heat shrink tubing over both wires and push it back out of the way. Twist all 4 ends together and bend them back over themselves so that they are secure and won't pull apart. Then slide heat tubing over all exposed copper and shrink. It will hold up just fine. I cut 4 inches off all my servo wired so I don't have that tangled mess in my RX box and it works great with no soldering required