PRACTICAL CHANGE SYSTEM: Due to the thread in the soldering iron adapter, the soldering tips can be changed very easily WITHOUT completely unscrewing the soldering iron. 3D PRINTER PARTS: 3D printer soldering tips are commonly used for 3D printers to print parts with hot melt copper nuts or to implant nuts on plastic. EASY TO USE: The small distance embedded in the pressed head avoids the plastic parts, so the head is not easily damaged to the plastic parts, and can be inserted into the plastic parts to a certain depth. 936 UNIVERSAL SOLDERING IRON TIPS: Soldering tips are interchangeable with standard 936 general soldering iron tips for use with M2 (M2.5 common), M3, , M5, M6 (1/4 inch), M8 and other hot melt nuts or inserts. BRASS MATERIAL: Heat set inserts are made of brass for better thermal conductivity and face to face contact to prevent nut skewing and facilitate quick insertion of nuts into plastic parts. Material: Brass Color as shown Package Contents: 1 x Embedding Tool kit Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.