Martin Authentic SP Phosphor Bronze Acoustic Guitar Strings

Get excellent tuning stability, corrosion resistance and playability for your go-to acoustic with these Martin Authentic SP Phosphor Bronze acoustic strings.

These strings are engineered with the performer in mind and they will always stand up to rigorous practice and performance schedules. Martin starts with the highest tensile-strength core wire, then tin-plate it on all six strings for added corrosion resistance; because what you don't see matters! When coupled with their highest quality wrap wire you get consistent true tone that you can count on song after song.

Get an overview of Martin Authentic Acoustic strings:


Martin Authentic SP Phosphor Bronze Acoustic Guitar Strings offer excellent tuning stability, corrosion resistance and great playability.
WARNING: Cancer and Reproductive Harm - www.p65Warnings.ca.gov.

Extra Light 6-String
- Gauge: 10-14-23-30-39-47

Custom Light 6-String
- Gauge: 11-15-23-32-42-52

Light 6-String
- Gauge: 12-16-25-32-42-54

Medium 6-String
- Gauge: 13-17-26-35-45-56

Light/Medium 6-String
- Gauge: 12.5-16.5-25.5-33.5-43.5-55
Dimensions and Weight in Packaging
Custom Light, MA535
Shipping Weight: 0.25 lbs
Shipping Dimensions: 6 x 5 x 1 in
Manufacturer Part Number (MPN): 41Y18MA535
Extra Light, MA530
Shipping Weight: 0.25 lbs
Shipping Dimensions: 6 x 5 x 1 in
Manufacturer Part Number (MPN): 41Y18MA530
Light, MA540
Shipping Weight: 0.25 lbs
Manufacturer Part Number (MPN): 41Y18MA540
Light/Medium, MA545
Shipping Weight: 0.25 lbs
Shipping Dimensions: 6 x 5 x 1 in
Manufacturer Part Number (MPN): 41Y18MA545
Medium, MA550
Shipping Weight: 0.25 lbs
Shipping Dimensions: 4 x 4 x 1 in
Manufacturer Part Number (MPN): 41Y18MA550
Light, MA540, 3-Pack
Shipping Weight: 0.25 lbs
Shipping Dimensions: 6 x 5 x 2 in
Manufacturer Part Number (MPN): 41Y18MA540PK3
Medium, MA550, 3-Pack
Shipping Weight: 0.25 lbs
Shipping Dimensions: 5 x 4 x 2 in
Manufacturer Part Number (MPN): 41Y18MA550PK3
MA535, Custom Light, 25-Pack
Shipping Weight: 2 lbs
Shipping Dimensions: 9 x 8 x 5 in
Manufacturer Part Number (MPN): 41BULKBOXMA535
MA540, Light, 25-Pack
Shipping Weight: 2.25 lbs
Shipping Dimensions: 9 x 8 x 5 in
Manufacturer Part Number (MPN): 41BULKBOXMA540
MA550, Medium, 25-Pack
Shipping Weight: 2.25 lbs
Shipping Dimensions: 9 x 8 x 5 in
Manufacturer Part Number (MPN): 41BULKBOXMA550

For support or warranty questions, please contact the manufacturer:
Phone: 610-759-2837

Martin Authentic SP

These strings are engineered with the performer in mind and they will always stand up to rigorous practice and performance schedules. Martin starts with the highest tensile-strength core wire, then tin-plate it on all six strings for added corrosion resistance; because what you don't see matters! When coupled with their highest quality wrap wire you get consistent true tone that you can count on song after song.

Martin Authentic SP Phosphor Bronze Acoustic Guitar Strings offer excellent tuning stability, corrosion resistance and great playability.

Custom Light, MA535

$7.49
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