Structurally, using a form of carbon powder mixed with an insulating material, which does not conduct electricity at all, forms most through hole resistors. This is mixed with a paste or resin to create a solid inner core of the resistor, the conductive path. The ultimate resistance of the device is determined by how much carbon fiber there is relative to the insulating material within the core, or the ratio between them. The more carbon, the lower the resistance. To protect the core, a plastic shell is often placed around it, and two thin wire terminals attach to each end.Through hole resistors are typically simple cylindrical components with a long terminal pins on either side which can be bent to conform to a variety of hole layouts on a PCB. Often they are color coded with an industry-standard code that displays the ohmage rating of the device. Through hole resistors have a wide range of variability, with the same package sizeable to accommodate an impedance of less than 1 ohm up through 10s of millions. The fixed designation in the title implies that there is a constant resistance that only may change very slightly during operation or with any sort of temperature variation.Shop Arrow’s range of through hole resistors today. Read more Read less