Feature: 1. Easy Installation: This printhead kit includes one printhead only; no additional accessories or tools are required. Simply insert the printhead to complete installation, saving time. 2. Material: The shell is made of high-quality ABS material, wear-resistant, and has been tested multiple times to ensure printhead performance and reliable printer operation. 3. High Performance: Upgraded 950 print head chip enables faster ink cartridge recognition, smooth ink flow, helps protect the printer, and delivers clear, vibrant prints. 4. Applicability: Compatible with HP OfficeJet Pro 8100, 8600, 8610, 8620, 8650, 251DW, 251. 5. Note: Exercise care when installing the nozzle. Always turn off and unplug the printer before installation. Specification: Item Type: Print Head Product Material: ABS Applicable Models: HP OfficeJet Pro 8100, 8600, 8610, 8620, 8650, 251DW, 251 Package List: 1 x Print Head Note: Solution for incompatibility: Reset the printer by following these steps. Turn on the printer if it is not already powered on. Wait for the printer to become completely idle. Disconnect the power cord from the back of the printer. Unplug the power cord from the wall outlet. Wait at least 60 seconds. Plug the power cord back into the wall outlet. HP recommends connecting the printer directly to a wall outlet. Reconnect the power cord to the printer. Turn on the printer if it does not power on automatically. Allow time for the printer to warm up. Lights may blink and the carriage may move during startup. Wait for the printer to complete warm-up and become completely idle before proceeding. If the issue persists after resetting, replace the original ink cartridge and ink.