Fishman offers 4 variations of this product with different dimensions and configurations – make sure you order the proper one for your instrument!
Most press-on knobs are made to fit a coarse 18-tooth knurled shaft potentiometer. Some Gibson-style knobs are available in both coarse 18-spline and fine 24-spline. If you currently have 24-spline knobs you may need replacement knobs designed for 18-spline shafts. For many screw-tightening knobs, the 6mm solid (plain) shaft is the correct option. If you are unsure of which pot you are replacing, please research and confirm before you order.