If you need this accessory urgently, you can buy it from our Aliexpress !
Link: https://www.aliexpress.com/item/1005004821145177.html
Please note: To upgrade Single Gear Extruder to Double Gear Extruder, you CANNOT directly buy this product, please contact email: linda@qd3dprinter.com to buy a complete set of upgrade accessories.
Please refer to the following image to check your adapter color: