This is the 3rd Generation heating cartridge compatible with nearly all 12v extruder systems. Thicker gauge wire and full high temperature thermal shielding make this an ideal upgrade for those looking for durability reliability, and performance. Higher Gage wire and better insulation = less voltage loss. This is fully compatible with the Wanhao i3v2.1, Monoprice Maker Select V2, and many more. Just make sure your printer is 12V. and is 5.9mm in diameter.