Expand for T12/900M Soldering Iron Functions: Include 2 heating tip adapters specially designed to for 936/T12 soldering iron and turn them into a portable heat insert pressing machine tool to expand their functions,Heating tip with M4 thread! M2-M8 Brass Knurled Nut: Wide range brass knurled nut embedded insertion tip heads include M2,M2.5,M3,M4,M5,M6,M8 to meet your most installation needs Easy to Use: Screw installation design easy to change different head model, no need to take off the soldering iron whole tip,just screw off the tip head then install the model head Better Performance: Tip head made from brass with high strength and good heat conduction ensure better heat insertion performance to get a smooth and clean insert than the normal soldering iron using 3D Printed Parts Essential Tool: Ideal for install brass knurled nut into your 3D printing parts enable you assemble and disassemble your projects easily, but won't ruin or contaminate your part rather than a normal soldering iron tip that either stuck or penatrate the insert hole Color: As Shown Material: Brass Package Contents: 1 * T12 Soldering Iron Tips 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.