The Volume adjustment knob is the most frequently and repeatedly used component in Bottle Top Dispensers. As the name indicates, it’s a small knob which is used for setting and adjusting volumes. In order to ensure the longevity of the knob itself and facilitate easy and efficient volume setting, this component conventionally operates on a screw type mechanism/technology. But, over time, users have reported that this technology comes with its own set of demerits.
It is commonly observed that users tend to over rotate a screw-based volume adjustment knob. In order to ensure that it is tightly secured, the knob is given an extra turn and because of this, it either gets too tight to be loosened again easily or breaks.
The knurling on the screw of a volume adjustment knob has been designed to offer better grip. In actual practice however, when the knob has been tightly secured because of over rotation, these grooves or knurls cause pain to the fingers and thumb whenever the user tries to loosen it.