Be sure to add me to your favorites list Replacement Black Colored Knob / Dial with Red Marker Line, for the 1980's Era Vintage RockTek Series of Guitar Effects Pedals, a Genuine Rock Tek Part This is a used replacement part for many of the Rocktek series of guitar effect pedals. It is for one of the knobs / dials used in those types of pedals. Please see my photos to see what this looks like. It seems that most if not all of the pedals in this series used these, a black colored dial with a red marker line. It shows some minor, normal wear but no damage. Price is for ONE of these knobs, and I have more than one available if you needed them. Thanks for looking! Check out my Store!