Detail 01
18:1 gear ratio
Provides fine pitch adjustment during tuning.
Product detailSKU #1500000429804
GroverProfessional Mandolin F Style 409 Series Black Button Tuning Machines Gold
1/2
Independent shopping perspective
The Korena take
Gold-finished Grover Professional Mandolin F Style 409 Series tuning machines with black buttons, intended for precise mandolin tuning and a vintage-leaning appearance. The 18:1 ratio is built around close pitch adjustments, and the staggered open worm-over gears are arranged for alignment and smooth operation. A die-cast plate and bell-top button screws complete the hardware. For replacement work, the stated 25/64-inch post-hole requirement is the first measurement to check.
Strong match
Who this is for
- Updating a mandolin with stock tuners where the existing post holes measure 25/64 inch.
Consider the trade-offs
When to look elsewhere
- Mandolins that do not use 25/64-inch tuner post holes.
What matters in use
The specifications, translated
Catalog numbers tell only part of the story. These are the details most likely to change how this product feels, sounds, or fits into a setup.
Detail 02
Staggered worm-over open gears
The open gears are arranged to maintain alignment for smooth operation.
Detail 03
Die-cast plate
Keeps the gears properly aligned.
Final check
Know before you order
- 01Verify that the mandolin has 25/64-inch post holes before treating these as a drop-in replacement.
Product questions
Before you decide
Straight answers to the questions shoppers most often ask about this product.
01Are these intended as replacement tuners?
They are designed as a drop-in replacement for many stock tuners when the post-hole size matches.
02What is the finish and button color?
They have a gold finish and black buttons.
Reference
Full specifications
The complete catalog record, organized around the decisions musicians make when comparing gear.
1 detailsBody & build
- Color
- Black
