Selective soldering is the process of selectively soldering of through hole (TH) components to printed circuit boards that could not be soldered in a reflow oven in a traditional surface-mount technology (SMT) assembly process. This usually follows an SMT oven reflow process; parts to be selectively soldered are usually surrounded by parts that have been previously soldered in a surface-mount reflow process, and the selective-solder process must be sufficiently precise to avoid damaging them.