Double Flare vs. Bubble Flare | What Flare for Brake Lines?

Sometimes you might wonder why the brake fluid leaks from the flared lines of the brake. To understand better, there are a number of reasons behind all this, depending on the quality of the flare you made as well as the type of flare. Therefore, before flaring on the lines of the brakes, it is good to master the information on the double flare vs. bubble flare.

In this article, I am going to discuss well-researched information on the main differences between the bubble flare and double flare to enable you to come up with the best that will satisfy your needs and demands. Besides, we have a comparison table for easy understanding.

Comparison between double flare and bubble flare 

Usually, the entire quality of the flare is a significant factor to consider when choosing your best. If you select a flare of low quality, it may lead to leakages on the brake fluid. Therefore, to get better quality flares, make sure that you use the right tool. Let’s now look at their comparison, as discussed below.

Double flare and bubble flare are two different flares. However, to obtain a double flare, it is a must to come up with a bubble flare first. The two flares are the standard flare you can find in the vehicles. This double flare is almost similar to that of the single flare, which is highly durable.

Additionally, most of the manufacturers prefer using a double flare on the brake lines, but you can as well get bubble flares in some vehicles which come from Europe.

The double flare is also called as SAE to some experts. Besides, it is also referred to as 450 flares. This type of flare is capable of handling different variant production. 

With the presence of the double flare, the far end line may doubles in the internal braking system of the vehicle. For proper folding over, it requires a single flares lip. However, double flare appears almost similar to that of a single flare.

Furthermore, double flare is the best flare in terms of sturdiness and durability compared to that of bubble flare. Double flare also is capable of handling very heavy pressure on the inner part of the braking system of the car.

On the other hand, the bubble flare is also referred to as ISO or DIN. They are most suitable and widely used by most vehicles in Europe. Bubble flare is the first step you make before creating the double flare.

Comparison table between double flare and bubble flare

Double flare
Double flare
Highly durable and sturdy
Less durable
Capable of handling very heavy pressure
Relatively handles at a lower pressure than double flare
Also referred to us SAE
Also known as ISO or DIN
Obtained from bubble flare
Made first before the double flare
How to Flare a Brake Line / Bubble Flare and Double Flare

FAQ’s regarding Double Flare vs. Bubble Flare

Is a single flare the same as a double flare?

The double flare is more durable and sturdy than a single flare. Additionally, single flares are not suitable for use in steel brake lines.

What type of flare is best for brake lines?

Automotive professionals prefer using both the flares, but double flare is the most commonly used in the brake line system.

What is the best brake line material?

Usually, the best brake line material is stainless steel since it is resistant to rust and punctures.


Having gone through the above article, I hope that you have gotten insight information between double flare vs. bubble flare. You can agree with me that double flaring is the most suitable for use. Therefore, ensure that you have a proper flaring to avoid any leakages on the braking system of your vehicle.

Now that you have the basics of the two flares, you can choose yours that you are comfortable with.

Also Read: Automotive fender roller tools.

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