This 9PCS Heat Insert Nut Iron Tip Kit is made of durable CNC brass with excellent heat conduction for safe and stable trimming. Compatible with standard 936 and Hakko FX-888D soldering irons, it offers 9 interchangeable tips for quick swapping. Ideal for 3D printing materials like ABS, PLA, nylon, and polystyrene, its perfect for deburring, cutting, sculpting, punching, and nut embedding. Also great for hot-melt crafts such as wood carving.