Good quality plastic head with a very clever and easy way of changing the trimmer line without hand mixing or needing Allen keys. However, in my opinion, it has 2-3 serious disadvantages. Firstly, it is quite wide in construction, so the radius of action of the trimmer line is reduced. Secondly, I cannot balance it perfectly in the center 100%. Additionally, the minimum you can put is 4 (2 doubles) or 8, so you will need to calculate that your trimmer is powerful enough to perform correctly.