Detail 01
18:1 gear ratio
Provides smooth, stable tuning according to the product description.
Product detailSKU #1500000429853
GroverProfessional Mandolin A Style 409 Series Black Button Tuning Machines Gold
1/2
Independent shopping perspective
The Korena take
For an A Style mandolin, Grover’s gold 409 Series machines use adjustable worm gears and die-cast plates to maintain gear-and-worm alignment for accurate tuning. The 18:1 ratio is built for controlled tuning adjustments, and the open worm-over gear layout retains a vintage-inspired look alongside black buttons. A 25/64-inch post hole is specified, and the included hardware supports their intended role as a drop-in replacement for existing tuners.
Strong match
Who this is for
- Replacing existing A Style mandolin tuners using the specified 25/64-inch post-hole size.
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
Adjustable worm gears and die-cast plates
Maintain gear-and-worm alignment for tuning accuracy.
Detail 03
25/64-inch post hole
A measurement to verify on the existing installation.
Final check
Know before you order
- 01Verify the 25/64-inch post-hole measurement before replacing existing tuners.
Product questions
Before you decide
Straight answers to the questions shoppers most often ask about this product.
01Is installation hardware included?
Yes. Hardware is included.
02What gear configuration do these use?
They use open gears in a modern worm-over configuration.
Reference
Full specifications
The complete catalog record, organized around the decisions musicians make when comparing gear.
1 detailsBody & build
- Color
- Black
