Detail 01
Adjustable open gears and die-cast plates
The plates are designed to maintain gear alignment.
Product detailSKU #1500000429859
GroverProfessional Mandolin Vintage A Style 409 Series Pearloid Button Tuning Machines Chrome
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Independent shopping perspective
The Korena take
Finished in chrome with pearloid buttons, these Grover 409 Series Vintage A Style machine heads combine adjustable open gears with a modern worm-under layout. Die-cast plates are designed to keep the gears aligned, and the 18:1 ratio provides precise tuning adjustment. Bell-top button screws maintain the series’ vintage detailing. For mounting, the listed measurements are a 25/64-inch post hole and 30.3 mm overall post length, so those dimensions are central to selecting them.
Strong match
Who this is for
- Mandolin installations matching the published 25/64-inch post-hole and 30.3 mm post-length measurements.
- Precise tuning adjustments from adjustable open gears and an 18:1 ratio.
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
18:1 gear ratio
Allows precise tuning adjustments.
Detail 03
25/64-inch post hole; 30.3 mm overall post length
These are the published mounting dimensions.
Final check
Know before you order
- 01Verify the 25/64-inch post-hole and 30.3 mm overall post-length measurements before installation.
Product questions
Before you decide
Straight answers to the questions shoppers most often ask about this product.
01What mounting dimensions are listed?
The machine heads specify a 25/64-inch post hole and a 30.3 mm overall post length.
02What button style does this version use?
This chrome version has pearloid buttons and bell-top button screws.
