Video tutorial on how to solder copper wire and apply heat shrink tube. The type of solder that was used was rosin core and the type of wire used in the video is cross link which is quite common in automotive or electronic applications. Rosin paste flux is not required for this application as we are using rosin core solder instead. Rosin is intended to help the solder flow better while also adhering to the objects you are working with. This method also works with standard strand wire. Electrical tape can be used to provide protection on the soldered joint, but shrink tube is a much better method. Shrink tube will provide a better insulation, looks cleaner, will last longer, and is much more resistant to moisture. Heat shrink normally comes in black, but can also be purchased in specific colors to match the wires you are working with. There is also heat shrink tube available that has an internal adhesive which allows for a perfect water tight connection. Be sure to solder in a well ventilated area.