4Bond Keratin Protein Smoothing STRAIGHTLINES


SKU: 32850

 The 4Bond Keratin Protein Smoothing STRAIGHTLINES Treatment is the most exciting and advanced innovation in smoothing and anti-frizz technology. Long lasting results of up to 5 months can be achieved depending on hair type, cleansing routine & maintenance.

Express service Instructions

Full Service Instructions



Fortify & Maintain - 4Bond STRAIGHTLINES provides enhanced shine while conditioning, fortifying and maintaining salon services.

Repair Any Damage - Specifically engineered to seal the hair cuticle and repair split ends that have incurred damage through chemical services such as: color, lightener, smoothing, straightening and thermal styling.

Natural Ingredients - Smart Target Technology, a first of its kind, infuses a Proprietary Blend of Polymers, Keratin, Quinoa, and Baobab Proteins rich in Amino Acids into the hair's cortex.


Shake bottle vigorously. Pour into bowl and let aerate 15 minutes. Cleanse hair twice with a Clarifying Shampoo. Dry hair.

Express Service: 50% Dry, Full Service: 100%

Dry Use gloves when applying product. Separate hair into 5 quadrants. Start at nape area. Begin with 1/2" sections, using an applicator brush, apply 1/4" from scalp. Alternate sections when applying product. Comb through each section thoroughly. Do not oversaturate.

Express Service: Process 20 minutes. Full Service: Process 30-45 minutes.

Rinse leaving a small amount of residue in hair.Dry hair 100% smooth.Flt iron 193-210 *C (380-410*F) until smooth and silky. Recommended, finish with 4Bond PROEXTEND service extender.

Our Proprietary 4Bond Complex

Advanced Polymer - Coats the hair and provides conditioning benefits such as ease of combing, hair alignment, antistatic effects and improved gloss.

Baobab Protein - Is one of the most versatile vegetable proteinsthat helps with frizz control, hair elasticity and provides intense conditioning resulting in smoother and softer hair.

Quinoa Protein - Quinoa is a rich source of 9 essential amino acids that can strengthen hair follicles naturally, repair hair by nourishing and hydrating the scalp.

Keratin Amino Acids - Provides protection by filling or replenishing damaged gaps in the outer hair cuticle with lost keratin making hair stronger and less prone to breakage.

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Frequently Asked Questions

During application if product does get on the scalp what will the client experience? If the goal is to be 1/4 in away from scalp is there no way to address tiny curly frizz around the hair line?

We "recommend" product application 1/4" from scalp to avoid any type of irritation. When combing product through, it is inevitable for it to get on the scalp, we just try our best to avoid applying the product DIRECTLY on the scalp. When you are done combing through your section and you feel you may need a little more product in those troublesome areas, that's totally fine to do so. Just do not oversaturate. Oversaturating creates an unnecessary build up on the hair and does not give the client the correct overall picture of the service.

What’s the risk for over saturating the hair?

Oversaturating creates an unnecessary build up on the hair and does not give the client the correct overall picture of the service. It does not harm the service in any way shape or form, but it is doing a disservice to the client by having them leave with a service that is not executed and/or portrayed correctly.

How strongly scented is this product? Is a mask required or suggested?

The scent is not strong. It is a very light/ mild scent. As with any chemical service, some people who are sensitive to certain smells/ scents may want to wear a mask/ or put a towel over their face. We recommend starting your service out with not wearing one, make sure to check in on the client throughout the service to see if they need anything to cover their eyes/ mouth.

Is this formulated with formaldehyde and if not what preservative is used instead for longevity?

There is no formaldehyde in the formula.

The instructions mention rinse after processing but leave a small amount of residual product? This step leaves a lot of room for variation. How is the outcome effected if too much or too little is rinsed out?

Our general rule of thumb is to count to 5 when doing your rinse. This is the perfect amount of time to rinse out any excess product and enough time to make sure there is still enough product in the hair.

When rinsing the hair, how do you know how much is enough while leaving some residue?

Feel, that's really it. Just make sure you don't rinse it all out. 

Is the proextend intended as a retail product for clients at home?

Yes, the ProExtend is intended for retail. It is utilized to extend the longevity of the smoothing service done in the salon. Extending and maintaining the Smoothing Service at home is a simple and effective way to add on to retail sales.

Is there specific after care info or instructions for clients like products to avoid?

The client should avoid anything with sulfates, sulfites and parabens. These ingredients will rough up the hair cuticle and in turn, have the keratin wash out faster. This goes for all products (shampoos & styling aids).

Can this service be performed immediately following any type of color service?

Yes, you can. The treatment will extend the life and seal the color in.

Is this a straightener or a relaxer?

It is a smoothing treatment. It is not meant to permanently straighten the hair, it is meant to smooth the hair, with results varying depending on application.

It's called a keratin protein smoothing treatment. what does it actually do to the hair?

It rebuilds keratin bonds and strengthens and smooths the hair, eliminates frizz.

What does leaving Straightlines in a suitable bowl for 10-15 min do?

It aerates the product to allow the product to breathe before application. This was recommended by the chemist to allow for better absorbency to the hair. I asked the same question and that was my response. 

Although Straightlines recommends a clarifying shampoo, would 4bond shampoo be suitable to use as well?

No, you should be using a clarifying demineralizing shampoo. all brands usually have this. Ours is called CDS in the smartsolutions brand.

After shampooing twice do you condition?

No, this is to remove any buildup in the hair and basically strip the hair of any minerals/impurities to prep for chemical smoothing treatment. Unlike color services we want the hair "clean" not "dirty" .

Do you only apply more Straightlines every second section?

Correct, when "combing" in the product, it  will overlap and we do not want to oversaturate as this will cause a buildup or "film" on the hair and can become gummy or sticky if too much product is used.

Why does it specify half an ounce of Straightlines per 15 inches of hair when other places it says 1.5 ounces per average head of hair?

This is just a guideline. Every service may be different, depending on hair type and length.  As I mentioned in question 11. We do not want to over-saturate the hair.... Use this as a good selling tool versus other brands..... less product, less waste, MORE MONEY in your pocket. You will typically use 1.5oz to 2oz (44ml - 60ml) per head

In the full service you leave it on the hair between 30-45 minutes. What will cause the variance?

This all depends on the length and texture of the hair.

In that 30 -45 minutes do you cap the hair for body heat? Do you also need to leave the hair in a dead straight position?

You can cap and leave in a straight position if possible. Not necessary as it will be difficult when capped.

What does ironing the hair do?

It straightens and allows the product to penetrate and absorb into the hair. 

Option 1: Hair can be colored first and the keratin service immediately after on the SAME DAY.
Option 2: Color first and keratin service ONE WEEK later. (Not any earlier)
Option 3: Keratin first and color TWO WEEKS later. (Not any earlier)

We recommend analyzing the clients hair for porosity, density, texture, and overall integrity before deciding on how you will execute your timing. All of these factors tie in to how you would execute the two services.

Straightening Abilities

Our 4Bond STRAIGHTLINES is a unique product made to smoothen the most stubborn of curly hair. SLT can be used as an express service made to smooth and provide anti-frizz agents. In addition it will strengthen and condition with our 4Bond building ingredients.

Fortify & Maintain

4Bond STRAIGHTLINES infuses a Proprietary Blend of Polymers, Keratin, Quinoa, and Baobab Proteins rich in Amino Acids into the hair’s cortex. SLT will provide enhanced shine while conditioning, fortifying, and maintaining salon services. It is specifically engineered to seal the hair cuticle and repair split ends that have incurred damage through chemical services.