The JBC Tools C105-103 Cartridge, Conical, Ø 0.3 S1, is appropriate for repairing and soldering very small-sized components at high precision. It works with NT105 Nano Soldering Iron and NP105 Nano Tweezers. It can last five times longer than other brands because of the Exclusive Heating System and the Sleep & Hibernation features and supplied with five units in the DC-A dispenser case.