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Home / Guitar Electronic Accessories / 21×12mm Plastic Knob for Tube Amp Potentiometer Switch Cap, Round Guitar Volume Control Knob

Attributes

Brand -
Category Musical Instrument Accessories / Guitar Electronic Accessories
Origin -
Material ABS Plastic
Outer Diameter 21 mm
Total Height 12 mm
Shaft Fitment 6.35 mm (1/4 inch)
Color Black
Surface Finish Matte Texture
Package Quantity 4 Pieces
Total Weight 35 grams
Knob Style Round Top
Compatibility Audio Potentiometers

5 reviews

A

Anonymous

Apr 12, 2026

Rating: 3/5

A Bit Tight

Functionality is fine but the fit was tighter than expected.

A

Anonymous

Feb 14, 2026

Rating: 5/5

Exact Dimensions

I measured them and they are exactly 21mm as described.

A

Anonymous

Feb 08, 2026

Rating: 5/5

Great Replacement

Replaced lost knobs on my guitar pedal board. Look great.

A

Anonymous

Feb 05, 2026

Rating: 5/5

Perfect Fit for Amp

These knobs fit my vintage amplifier pots perfectly. Very happy with the size.

A

Anonymous

Jan 29, 2026

Rating: 4/5

Good Quality Plastic

Sturdy construction but required a bit of force to push on.

5 FAQ

Q: Can I buy more than 4 pieces?

A: Yes, please check our bulk listing or contact support.

Q: Is adhesive included in the package?

A: No adhesive is needed as these are push-fit knobs.

Q: Do these fit split shaft potentiometers?

A: These are designed primarily for solid shafts but may fit some split shafts.

Q: What is the return policy?

A: We offer a 30-day return policy for unused items.

Q: Are these heat resistant for tube amps?

A: Standard plastic material. Avoid direct contact with hot tubes.

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