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4LifetimeLines 3/16 in M10x1.0 inverted flare stainless steel tube nut (LTN31SS), view 1
4LifetimeLines 3/16 in M10x1.0 inverted flare stainless steel tube nut, view 2
4LifetimeLines 3/16 in M10x1.0 inverted flare stainless steel tube nut, view 3
4LifetimeLines 3/16 in M10x1.0 inverted flare stainless steel tube nut, view 4
4LifetimeLines 3/16 in M10x1.0 inverted flare stainless steel tube nut, view 5
4LifetimeLines 3/16 in M10x1.0 inverted flare steel tube nut (LTN31), view 1
4LifetimeLines 3/16 in M10x1.0 inverted flare steel tube nut, view 2
4LifetimeLines 3/16 in M10x1.0 inverted flare steel tube nut, view 3
4LifetimeLines 3/16 in M10x1.0 inverted flare steel tube nut, view 4
4LifetimeLines 3/16 in M10x1.0 inverted flare steel tube nut, view 5
4LifetimeLines 3/16 in M10x1.0 inverted flare black oxide coated steel tube nut (LTN31BO), view 1
4LifetimeLines 3/16 in M10x1.0 inverted flare black oxide coated steel tube nut, view 2
4LifetimeLines 3/16 in M10x1.0 inverted flare black oxide coated steel tube nut, view 3
4LifetimeLines 3/16 in M10x1.0 inverted flare steel tube nuts, 50 pack (LTN31-50), view 1
4LifetimeLines 3/16 in M10x1.0 inverted flare steel tube nuts, 50 pack, view 2
4LifetimeLines 3/16 in M10x1.0 inverted flare stainless steel tube nut (LTN31SS), view 1
4LifetimeLines 3/16 in M10x1.0 inverted flare stainless steel tube nut, view 2
4LifetimeLines 3/16 in M10x1.0 inverted flare stainless steel tube nut, view 3
4LifetimeLines 3/16 in M10x1.0 inverted flare stainless steel tube nut, view 4
4LifetimeLines 3/16 in M10x1.0 inverted flare stainless steel tube nut, view 5
4LifetimeLines 3/16 in M10x1.0 inverted flare steel tube nut (LTN31), view 1
4LifetimeLines 3/16 in M10x1.0 inverted flare steel tube nut, view 2
4LifetimeLines 3/16 in M10x1.0 inverted flare steel tube nut, view 3
4LifetimeLines 3/16 in M10x1.0 inverted flare steel tube nut, view 4
4LifetimeLines 3/16 in M10x1.0 inverted flare steel tube nut, view 5
4LifetimeLines 3/16 in M10x1.0 inverted flare black oxide coated steel tube nut (LTN31BO), view 1
4LifetimeLines 3/16 in M10x1.0 inverted flare black oxide coated steel tube nut, view 2
4LifetimeLines 3/16 in M10x1.0 inverted flare black oxide coated steel tube nut, view 3
4LifetimeLines 3/16 in M10x1.0 inverted flare steel tube nuts, 50 pack (LTN31-50), view 1
4LifetimeLines 3/16 in M10x1.0 inverted flare steel tube nuts, 50 pack, view 2

4LifetimeLines 3/16" M10x1.0 Inverted Flare Tube Nuts, 10 or 50 Pack

$15.00
5.0
Rated 5.0 out of 5 stars
2 Reviews

SKU: LTN31

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Not sure what size you need? 3/16" is the most common brake line size — check the size chart or call 1 (855) 928-4024.

The 4LifetimeLines 3/16" M10x1.0 Inverted Flare Tube Nut fits 3/16" brake line with an inverted flare and M10x1.0 metric threads. Choose steel, black oxide coated steel or stainless steel, in a 10-pack, or a 50-pack in steel.

What's in the box

  • 10 or 50 tube nuts, 3/16" M10x1.0 inverted flare, in the material you choose

Where to use it

Use these nuts when replacing or repairing 3/16" brake line that connects with M10x1.0 inverted flare fittings. The 50-pack suits shops doing repeat brake line work.

Questions

Will they work with copper-nickel line? Yes. They work with steel, copper-nickel, copper-coated steel, PVF-coated and stainless steel line.

What flare do they need? An inverted flare on 3/16" line, with M10x1.0 threads on the mating fitting.

Steel, black oxide or stainless? All three fit the same way. Pick the material that matches the rest of your fittings or the look you want.

Warranty and support

Covered by the 4Lifetime Limited Lifetime Warranty (see 4lifetimelines.com/pages/warranty). Questions? Email hello@4lifetimelines.com or call 1 (855) 928-4024, Monday–Friday, 9:00 AM–5:00 PM ET.

Tube size: 3/16" (4.75 mm)
Thread: M10x1.0 (metric)
Flare type: Inverted
Material options: Steel, black oxide coated steel, stainless steel
Pack options: 10 (all materials); 50 (steel)
Line compatibility: Steel, copper-nickel, copper-coated steel, PVF-coated and stainless steel line
Application: Brake line
Vehicle fit: Universal (not vehicle-specific)
SKUs: Steel 10: LTN31; Steel 50: LTN31-50; Black oxide 10: LTN31BO; Stainless 10: LTN31SS
Warranty: 4Lifetime Limited Lifetime Warranty

  • 4.8★ from nearly 4,000 Amazon ratings
  • Free US shipping on orders $50+
  • Ships same day when ordered by 2 PM ET (Mon–Fri)
  • Lifetime warranty on every product

Lifetime Quality, Covered — for Life

Zero Risk, Maximum Confidence

Built to Endure. Guaranteed to Perform.

One-Time Purchase. Lifetime Assurance.

Lifetime Quality, Covered — for Life

Zero Risk, Maximum Confidence

Built to Endure. Guaranteed to Perform.

One-Time Purchase. Lifetime Assurance.

Lifetime Quality, Covered — for Life

Zero Risk, Maximum Confidence

Built to Endure. Guaranteed to Perform.

One-Time Purchase. Lifetime Assurance.

Lifetime Quality, Covered — for Life

Zero Risk, Maximum Confidence

Built to Endure. Guaranteed to Perform.

One-Time Purchase. Lifetime Assurance.

Lifetime Quality, Covered — for Life

Zero Risk, Maximum Confidence

Built to Endure. Guaranteed to Perform.

One-Time Purchase. Lifetime Assurance.

Lifetime Quality, Covered — for Life

Zero Risk, Maximum Confidence

Built to Endure. Guaranteed to Perform.

One-Time Purchase. Lifetime Assurance.

Lifetime Quality, Covered — for Life

Zero Risk, Maximum Confidence

Built to Endure. Guaranteed to Perform.

One-Time Purchase. Lifetime Assurance.

5.0
Rated 5.0 out of 5 stars
Based on 2 reviews
100%would recommend this product
2 reviews
  • Rated 5 out of 5 stars
    3 years ago
    Good product

    Good product

    BS
    Bunchhoung S.
  • Rated 5 out of 5 stars
    4 years ago
    No problem at all! Good Quality

    I use these often, so much better then drilling out old ones and trying to reuse them. Plus it makes for a better quality job in the long run especially when using copper Nickle line.

    RL
    RICO L.
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Built to Endure

BUILT TO ENDURE

No Weak Points. No Compromises.

Lifetime Warranty

LIFETIME WARRANTY

One Purchase. Lifetime Coverage.

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TRADE FRIENDLY

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The 4Lifetime Difference

Engineered to Last. Backed for Life.

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Built with materials and workmanship we trust. No shortcuts.

A Smart, Risk-Free Buy

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Buy once. Be done.
This isn’t a temporary fix — it’s a long-term solution. Built-in confidence. Zero guesswork.

Straightforward. No Fine Print.

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What you see is what you get.
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As long as you own it, we’ve got your back.

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Meets SAE / OE specifications

Easy returns — no restocking games

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100+ 5 star reviews

“.. easy to get the part you need, when you need it.”

Jackson

Great Experience

Great received day early good product this is 3rd time doing business with 4LifetimeLines

Happy Customer

Great product!! I’ve ordered these before and they are great quality! I’ll be back again.

Excellent

Excellent product shipped quickly and inexpensively. I will be ordering again.

Ideal Products

Ideal stuff for fabricating brake lines brake lines at a very good price.Kit very well covers the materials for doing the whole brake line system.

Reasonable price and fast shipping!

I'll be back again!

Great Seller!

Great seller to deal with. Fast shipping and great products.

Great products, competitive prices, and fast shipping. Communication is also top notch.

This was my first purchase and the experience has been fantastic. Great products, competitive prices, and fast shipping. Communication is also top notch.

Great products, competitive prices, and fast shipping.

This was my first purchase and the experience has been fantastic. Great products, competitive prices, and fast shipping. Communication is also top notch.