Hi and thanks for the interest!
Yes, they are indeed push-on Boss replacement knobs.
Part of my OCD requires that all my pedals must have them (the SansAmp VT Bass has them too!)
If the spacing of the knobs is too tight to allow for this, (as on the other pedals) I use the push on black rubber type with a white stripe.
I don't have problems with my eyesight (except for being colour blind) but the bigger the white stripes on knobs, the easier it is to see settings with a downward glance.
In fact, I routinely switch out all LEDs with the larger 5mm blue type for my colourblindness, as it's the easiest colour for me to see. Dull red or green LEDs are almost invisable to me sometimes!