I was wondering how many people may know what it is. That's why I posted a picture without the packaging. You obviously know that it's an alloy head for a brushcutter. Other than that, you looked at the file name.
Those alloy heads need replacing before they wear down too far, or they can become dangerous.
If you look at the text on the aluminium casting, it reads:
(WARNING) WHEN RUB STRIP GONE, UNIT REQUIRES REPLACEMENT.
Well, many years ago, I learnt the hard way, and the alloy head shattered into pieces, and one of the pieces hit my leg and dropped me to the ground. Some pieces were found many metres down the road. I was lying on the ground with the brushcutter still running, and my wife came out of the house wondering what all the fuss was about. My lower leg was in a bit of a mess. She wanted to take me to the hospital, but I didn't go.