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Home / Other Components / 21×12mm Plastic Knob Tube Amp Power Amplifier Audio Potentiometer Switch Cap Guitar Volume Control Round Knob

Attributes

Brand -
Category Electronic Components Market / Other Components
Origin -
Material High-quality ABS Plastic
Dimensions 21mm Diameter x 12mm Height
Shaft Fit 6mm Split Shaft (Standard)
Color Matte Black
Shape Round Dome Style
Compatibility Electric Guitar, Bass, Tube Amps
Package Quantity 2 Pieces per Pack
Weight 8 grams (pair)
Finish Non-slip Textured Surface
Installation Push-on Fit (No Screws Required)

6 reviews

A

Anonymous

Mar 29, 2026

Rating: 5/5

Exactly as described

The dimensions are accurate. They slide right onto the 6mm shaft and stay put. Very happy with this purchase for my DIY pedal project.

A

Anonymous

Mar 24, 2026

Rating: 4/5

Good value for the price

Bought these to replace some worn-out knobs on an old amp. They look great and function well. One knob was slightly loose, but a tiny bit of glue fixed it.

A

Anonymous

Mar 23, 2026

Rating: 3/5

Decent but basic

They do the job. The plastic feels a bit lightweight compared to metal knobs, but for the price, you can't complain. Good for backups.

A

Anonymous

Mar 17, 2026

Rating: 5/5

Great replacement parts

I needed specific size knobs for a vintage amplifier restoration. These 21x12mm caps were exactly what I needed. Fast shipping too.

A

Anonymous

Mar 09, 2026

Rating: 5/5

Perfect fit for my Stratocaster

These knobs fit perfectly on my guitar's volume pots. The black finish matches the hardware nicely, and they feel sturdy despite being plastic.

A

Anonymous

Mar 04, 2026

Rating: 5/5

Smooth operation

No scratching on the potentiometer shafts. The inner grip is strong enough to turn the pot without slipping. Highly recommend for guitarists.

5 FAQ

Q: What is the exact height of the knob?

A: The total height from the base to the top of the dome is 12mm, as specified in the product title and attributes.

Q: Will these fit a CTS potentiometer?

A: Yes, these knobs are designed for standard 6mm split shafts, which includes most CTS pots used in guitars and amps.

Q: Are these sold individually or in pairs?

A: This listing is for a pack of 2 knobs. If you need more, please adjust the quantity at checkout.

Q: Do these come in white?

A: Currently, this specific model is only available in Matte Black. Please check our store for other color options in different listings.

Q: Can I use these on a solid shaft pot?

A: These are specifically designed for split (slotted) shafts. They may not grip securely on solid shafts without modification or adhesive.

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