Yeah, we've played the phone cord soldering game a few times to make extensions but even after you get through the tricky soldering, finding heatshrink that small for each individual wire is impossible. PITA! Also, for clarity, the colors that the cord have on each end don't matter at all, as long as they are the same top to bottom on each end of the cord (I think some types of phone cord swap the two center wires as they run along the line for some reason or some application)...