Cheaper does not go, limited functionality

If you press the Dimmer, has that done very carefully, because otherwise drops the knob. The holder is not tight enough. There are inside two plastic tabs with wire wrapped (!).

Switching on and off does not go each time. You have to place in the center of the knob and then press with decent power until it clicks finger very precisely.

I also have variations in brightness at about medium brightness, the light is always oscillating light and dark.