This handpiece fitted my FR-300 perfectly and started working as intended. If you read reviews that say the attachments are false or fake, you are wrong. These are original Hakko tips from Japan. What some people don't know is that the nozzle hole is sealed with "tinning" (lead-free solder) from the factory. To clean, all you have to do is place the tip on the tool, heat to operating temperature, and run the vacuum for a few seconds to remove the solder. That's all. Couldn't be easier. The packaging even states that the nozzle is factory tinned with lead-free solder. Obviously some people don't read the packaging and do stupid things like drill out the nozzle before trying to use it. RTFM.