Be sure to add me to your favorites list Genuine Roland Replacement Parameter / Volume Knob / Dial Part for the 90's classic GR-1 Guitar Synthesizer. This is a very good condition, replacement knob / dial part for the very popular 1990's era Roland GR-1 Guitar Synthesizer. Unfortunately, these are sometimes lost, so here's a genuine ROLAND replacement part! This is in very good condition, and is a genuine Boss / Roland part. This type of knob / dial is used for all of the parameter as well as the volume control on the GR1, and pops right onto the stem of whichever control you need it for. Price if for one (1) knob, and I have a few of these available. You can get one or more. See my photos. If you have a GR-1 that's missing some knobs, this is exactly what you need for your guitar synth! Genuine Roland Part, made in Japan! Thanks for looking, Check out my Store!