From Allparts:
Gotoh concentric stacked knob set with indicator dot. Fits Bartolini, Duncan, EMG concentric pots, with set screws
Features and Specifications
Bottom Knob (VK18) - 18mm OD, 8.1mm ID, 10mm tall
Top Knob (VK15) - 15mm OD, 6mm ID, 13mm tall
Made in Japan
