I have only positive comments to make:
1) No more wasting time with painful screwing and unscrewing of the head to change the trimmer line.
2) No more interruptions to change the trimmer line.
3) Changing the trimmer line now takes only half a minute without screwing and unscrewing the head. However, you need to have pre-cut trimmer line pieces with a maximum length of 40 centimeters.
4) The sample trimmer line that comes with the head is very durable. The ground I trim every year is rocky, causing trimmer lines to wear out quickly, even when using thicker ones. However, this specific one lasted without needing a replacement.
5) I have automatic plastic heads and other aluminum heads in my arsenal that require screwing and unscrewing to change the trimmer line. Well, I have eliminated all of them and now only use this head.

Without exaggeration, I consider this head to be unique, and I genuinely applaud the person who designed it.