Complete product information
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"title": "Martin MP550T Era Acoustic Guitar Strings Medium",
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"items": [
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"title": "5.0 out of 5 stars They make a difference",
"body": "These strings really kind of tripped me out! When I first played them, I could tell the difference in the smooth sound or even in heavy strum! Really nice and they made me wish I had found these strings 25 years ago! Read more",
"author": "Timothy Redmond",
"rating": 5,
"date": "February 24, 2026",
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{
"title": "5.0 out of 5 stars Highly recommended! Excellent quality.",
"body": "The media could not be loaded. These strings are of exceptional quality. Martin expertly engineered a string that maximizes performance, delivering an outstanding blend of classic and modern acoustics. They feel superb, and the individual strings are clearly distinguishable, preventing accidental mix-ups—a mishap I previously made the first time I decided to restring myself. They maintain excellent tuning stability when properly stretched. I am definitely purchasing more. I actually prefer Martin strings over Elixir. Read more",
"author": "Alvin Malave",
"rating": 5,
"date": "March 1, 2026",
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{
"title": "5.0 out of 5 stars Great sound",
"body": "Good replacement for my Martin standards Read more",
"author": "Lisa",
"rating": 5,
"date": "February 10, 2026",
"verified": true,
"images": []
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{
"title": "5.0 out of 5 stars Great tone!",
"body": "Want that deep throaty Martin tone…here ya go! Not as slinky as Elixirs, but the tone is worth it, and honestly, they feel just fine. So far, I love them! Read more",
"author": "Danny",
"rating": 5,
"date": "February 8, 2026",
"verified": true,
"images": []
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{
"title": "5.0 out of 5 stars Quality from Martin",
"body": "Best Martin string yet! Slightly bigger gauge than Elixirs. Read more",
"author": "Tracy Davis",
"rating": 5,
"date": "February 24, 2026",
"verified": true,
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{
"title": "5.0 out of 5 stars Worth the money",
"body": "These are the strings I've been searching for.what an incredible sound. Read more",
"author": "Ron Dums",
"rating": 5,
"date": "February 11, 2026",
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{
"title": "5.0 out of 5 stars Martin Era strings : A lively, balanced tone.",
"body": "I was pleasantly surprised by the new Era Martin strings. They seem to have all the things I love in a string all wrapped up in one. They are treated thought don’t feel coated, yet are fairly smooth in feel with minimal squeak action. The sound, while subjective, is lively, articulate, while remaining well balanced across the frequency spectrum. I do notice some black on my fingers, though I react to some strings more than others, especially uncoated. The D’Addario XS and Elixir’s are the only ones that have no reaction with my fingertips. My favorite strings overall are the D’Addario XS, perhaps followed by these new Era strings, depending on how their lifespan pans out. I’ve had them on a Collings OM for a week, and they sing just like they did on day one, so good start! Ooh, and they seem to hold tuning well, though I’ve found nothing as unwavering as the XS, especially for the alternate tunings I use. At 17.99$ a set, they Era’s are less than XS and Nano’s, though in my opinion they’d be a real value at 15$ a set. I’m very happy with them so far, and congrats to Martin on releasing a new offering! Read more",
"author": "Troy Rickertsen",
"rating": 5,
"date": "January 25, 2026",
"verified": true,
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{
"title": "4.0 out of 5 stars Good if you like think stings",
"body": "My sine says these are okay I think it's a personal preference. He thinks they are too think but someone else could like that. I'm going to say these are like food...subjective to the person. There is nothing wrong with them and they are sturdy and sound good. They are just not for him. Read more",
"author": "T. Counts",
"rating": 4,
"date": "December 13, 2025",
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"short_description": "Built to achieve unmatched tone and playability, Martin Era strings set a new standard for what a phosphor bronze acoustic guitar string can be. Combining the best technologies from the Martin Strings lineup, Martin Era strings feature a patented Lifespan treatment to protect against corrosion, Flexible Core construction to enhance fretability and comfort, and silk-wrapped ball ends—designed with vintage instruments in mind and as a premium touch that symbolizes Martin’s handcrafted string-making history.",
"about_this_item": "Built to achieve unmatched tone and playability, Martin Era strings set a new standard for what a phosphor bronze acoustic guitar string can be. Combining the best technologies from the Martin Strings lineup, Martin Era strings feature a patented Lifespan treatment to protect against corrosion, Flexible Core construction to enhance fretability and comfort, and silk-wrapped ball ends—designed with vintage instruments in mind and as a premium touch that symbolizes Martin’s handcrafted string-making history. Features a patented Lifespan treatment to protect against corrosion; Flexible Core construction to enhance fretability and comfort, and silk-wrapped ball ends; Designed with vintage instruments in mind and as a premium touch that symbolizes Martin’s handcrafted string-making history; .013-.056 Rated 4.6 out of 5. Customers praise these guitar strings for their excellent sound, with one noting their throaty Martin tone.",
"long_description": "Built to achieve unmatched tone and playability, Martin Era strings set a new standard for what a phosphor bronze acoustic guitar string can be. Combining the best technologies from the Martin Strings lineup, Martin Era strings feature a patented Lifespan treatment to protect against corrosion, Flexible Core construction to enhance fretability and comfort, and silk-wrapped ball ends—designed with vintage instruments in mind and as a premium touch that symbolizes Martin’s handcrafted string-making history.\n\nHighlights: Features a patented Lifespan treatment to protect against corrosion Flexible Core construction to enhance fretability and comfort, and silk-wrapped ball ends Designed with vintage instruments in mind and as a premium touch that symbolizes Martin’s handcrafted string-making history .013-.056\n\nKey details: Item Weight: 1.94 ounces | Package Dimensions: 5.04 x 4.33 x 0.63 inches | Customer Reviews: 4.6 4.6 out of 5 stars (78) 4.6 out of 5 stars | Color Name: Metallic Bronze | String Gauge: Medium | String Material: Bronze | Material Type: Bronze | Size: Medium\n\nSizes may include: S, M, L, XL.\n\nCustomer feedback: 4.6/5 average rating.\n\nCustomers say: Customers praise these guitar strings for their excellent sound, with one noting their throaty Martin tone.\n\nReview snippets: These strings really kind of tripped me out! When I first played them, I could tell the difference in the smooth sound or even in heavy strum! Really nice and they made me wish I had found these strings 25 / The media could not be loaded. These strings are of exceptional quality. Martin expertly engineered a string that maximizes performance, delivering an outstanding blend of classic and modern acoustics. They feel superb, and the individual strings are clearly distinguishable, preventing\n\nFrom the manufacturer Martin ERA Strings Introducting Martin ERA strings because your last note should sound as good as your first. These are our most comfortable and durable strings yet, combing high-tensile tin-plated core technology, Flexible Core construction, and advanced Lifespan treatment so you can play longer without losing tone or feel. With distinctive red Marquis silk-wrapped ends, this is a bold new chapter in a legacy built on timeless tone. Built to achieve unmatched tone and playability Martin Era strings set a new standard for what a phosphor bronze acoustic guitar string can be. Combining the best technologies from the Martin Strings lineup, Martin Era strings feature a patented Lifespan treatment to protect against corrosion, Flexible Core construction to enhance fretability and comfort, and silk-wrapped ball ends designed with vintage instruments in mind and as a premium touch that symbolizes Martin’s handcrafted string-making history.",
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