Joe Knows Electronics 1/2W 86 Value 860 Piece Resistor Kit Most competitors use iron wire. We use copper wire to improve conductivity between resistor and circuit. Extra thick lead wires are included. This improves the ability to insert the legs of the resistor into a solderless breadboard. Each value is in an individual bag. Never get parts mixed up and waste time reading color bands to sort them. Every value is in order from least to greatest. Never waste time finding an ohm value. The box features a lid which can be opened and closed repeatedly and stays closed in any orientation. The box isnt just a tool to get the resistors to you but a tool for ongoing organization. The box is designed to fit the bags of parts with precision so that they dont fall over, get out of order, and make your life difficult. You can count on these parts being organized every time you open the box, even if the box is being thrown around in a toolbox.