The Heat Set Insert Tool Soldering Iron Tips by VECO-T is a reliable and efficient tool for soldering & melting tasks. Ideal for professionals and DIY enthusiasts alike, this tool features M2, M2.5, M3, M4, M5, M6, and M8 thread inserts for various soldering needs. Upgrade your workshop with this versatile and high-quality soldering iron tip set. It includes a C245 soldering cartridge & seven threaded inserts that screw onto the cartridge tip, which then heats up the insert. Great for use on plastics, soldering barrels & other thru-hole applications on PCB's.