For many years, we custom modified a KM20 6mm spline fit knob with a grub screw fixing for plain shaft rotary switches. This was a time consuming and costly process so we really had to find an alternative. This knob which whilst not identical to he KM20, is a close match. Both are 20mm diameter, black anodised aluminium although this one is solid whereas the KM20 is an anodised shell with a plastic insert. The main difference is their height, this knob is 14mm but the KM20 is 17mm. The knurling is also different but despite this, they are in keeping with the quality look of the KM20.

Specification:

1. Black knob with marker line
2. For plain 4mm shafts like our rotary wafer switches
3. Grub screw fit
4. Black anodised finish
5. Straight cut features
6. Diameter 20mm
7. Overall height: 14mm (KM20 is 17mm)
8. Shaft depth: 11.5mm, KM20 is 15mm, your choice as to whether to have a longer shaft length and see some of the pot fixing nut or to have a shorter shaft length resulting in the knob height differeing to the KM20.