Cable assemblies include at least a first wire and a second wire. The wires are enclosed, using injection molding, by a respective layer of thermo-resistant material. During the injection molding, the first wire and second wire are kept substantially straight so as to avoid kinks in at least one of the first wire and the second wire that can develop subsequent to the molding if a wire is not substantially straight. The tension associated with the first wire and the second wire is kept within a predetermined range or below a predetermined threshold. The predetermined range/threshold depends on a temperature associated with the injection molding. The injection molding can provide a zip structure over the wires such that the zip structure can be zipped-together and zipped-apart to prevent entanglement of the wires when used by a user.