K18 HeatBounce conditioning heat protectant bottle on a pink background

K18 leave-in conditioner bottle with promotional text on a colorful background

HeatBounce conditioning heat protectant 4oz

Before and after comparison of a woman's hair with K18 HeatBounce product.

Before and after comparison of a woman with hair treated using K18 products.

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Promotional graphic for HeatBounce heat protectants with a scientific diagram of hair follicle and text about heat protection.

K18 HeatBounce heat protectant and oil on a colorful background with text highlighting features.

Woman with styled hair holding a bottle of K-8 hair product, with text about heat protection and breakage reduction.

K18 Heatbounce Heat protectant with ressilicore heat-shielding technology on a pink background

K18 heat bounce and hair mask products on a pink background with text about damage repair and protection.

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Three women with styled hair against a colorful background with text about hair care.

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4.8

Rated 4.8 out of 5 stars

375 Reviews

HeatBounce conditioning heat protectant

Name: HeatBounce conditioning heat protectant 4oz
Brand: K18Hair
SKU: K18-35092
Price: 48.00 USD
Availability: InStock
Rating: 4.8 (375 reviews)

The future of heat protection

HeatBounce conditioning heat protectant 4oz $48.00

Description

This leave-in conditioning heat protectant detangles, softens, and delivers deeper heat protection than ever before*—for 85% less breakage after blow drying⁷.

How to use

Apply throughout sectioned hair, brushing through to help with even distribution. Less is more. Start small and build as needed. Hair should feel soft and tangle-free, but not coated.

Use on towel-dried hair before blow drying and on dry hair before hot tools

More to know

resilicore™ heat-shielding technology is inspired by proteins in nature that can withstand extreme temperatures. Unlike traditional heat protectants that only coat the cuticle, the size + molecular makeup of resilicore™ allows it to penetrate deeper than ever before*, into hair's inner cortex where heat damage can occur, forming a protective shield that fortifies from within.

Conditioning blend conditions, softens, and detangles even damaged hair

Created for all hair types + textures. Can be used on extensions.

Key benefits

Protects from heat up to 450°F

85% less breakage after blow drying⁷

Lightweight formula conditions, softens, and detangles even damaged hair

*Heat protection observed on hair in clinical testing after application of HeatBounce and use of 450℉ (232℃) flat iron on dry hair.

¹Results observed as a reduction in hair breakage in scientific testing after application of HeatBounce and use of 450℉ (232℃) flat iron on dry hair.

²Results observed as an increase in protein stability in scientific testing after application of HeatBounce on damp hair and exposure to 450℉ (232℃) flat iron on dry hair.

³Results observed as a reduction in color change in scientific testing after application of HeatBounce on dry hair and use of 450℉ (232℃) flat iron.

⁴Results observed as a reduction in hair breakage in scientific testing after application of HeatBounce on dry hair and use of 450℉ (232℃) flat iron.

⁵Results observed as a reduction in hair breakage in scientific testing after application of HeatBounce on dry hair and use of 450℉ (232℃) flat iron.

⁶Results observed as an increase in protein stability in scientific testing after repeated exposure to UV and HeatBounce application.

⁷Reduction in hair breakage observed in clinical testing after application of high heat blow dry on wet hair.

Ingredients

Water (Aqua) (Eau), Cellulose Gum, Isopentyldiol, Propanediol , Cetearyl Alcohol, Isopropyl palmitate, Sodium Benzoate, C13-15 alkane, sh-Oligopeptide-78 s-Fruit Fly Oligopeptide-1, (sh-Oligopeptide-78 s-Fruit Fly Oligopeptide-1) Peptides, Laurdimonium Hydroxypropyl Hydrolyzed Barley Protein, Helianthus Annus (Sunflower) Seed Oil , Oryza Sativa (Rice) Bran Extract, Helianthus Annuus (Sunflower) Extract, Rosmarinus Officinalis (Rosemary) Leaf Extract, Tocopherol, Behentrimonium Chloride, Brassicatrimonium Chloride, Gluconolactone, Arginine, Coco-Glucoside, Lactic Acid, Cellulose, C12-20 Alkyl Glucoside, Citric acid , Potassium Sorbate, Benzyl Alcohol, Isopropyl Alcohol, C14-22 Alcohols, Fragrance (Parfum), Amyl Salicylate, Benzyl Salicylate, Citronellol, Citrus Aurantium Peel Oil, Dimethyl Phenethyl Acetate, Geraniol, Geranyl Acetate, Isoeugenyl Acetate, Limonene, Linalool, Linalyl Acetate, Pinene, Tetramethyl Acetyloctahydronaphthalenes, Vanillin.

pairs well with

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Interdimensional biotech reverses bounce-depleting damage for 2-day hold

Description

This leave-in conditioning heat protectant detangles, softens, and delivers deeper heat protection than ever before*—for 85% less breakage after blow drying⁷.

got questions?

Get started here

Is HeatBounce activated by heat?

No, HeatBounce does not need to be activated to protect from heat.

Do I have to wait to use heat after applying HeatBounce?

No, you can blow dry or use hot tools immediately after applying HeatBounce.

How is HeatBounce different from traditional heat protectants?

HeatBounce is powered by resilicore™ heat-shielding technology, an innovation inspired by resilin—a natural protein that can withstand extreme temperatures. Unlike traditional heat protectants that only coat the outside cuticle layer of hair, the size + molecular makeup of resilicore™ allows it to penetrate deeper than ever before*, into the cortex where heat damage can occur, forming a protective shield that fortifies from within.

*Heat protection observed on hair in clinical testing after application of HeatBounce and use of 450℉ (232℃) flat iron on dry hair.

What’s the difference between molecular repair hair oil and HeatBounce?

While the molecular repair hair oil and HeatBounce have heat protection benefits, HeatBounce defends against heat from the cuticle¹ to the cortex², going as deep as heat damage goes to help protect against color fade, dry feeling, dullness, and breakage. The oil delivers traditional heat protection on the outer layers of hair and clinically proven damage repair.
¹Results observed as a reduction in hair breakage in scientific testing after application of HeatBounce and use of 450℉ (232℃) flat iron on dry hair.
²Results observed as an increase in protein stability in scientific testing after application of HeatBounce on damp hair and exposure to 450℉ (232℃) flat iron on dry hair.

When do I use HeatBounce in my routine?

After shampooing, apply the K18 mask (wait 4 minutes) or DAMAGE SHIELD conditioner. Then, apply HeatBounce and AstroLift™ before blow drying or air drying. Use HeatBounce again before any hot tools. Finish with K18 oil and use AirWash™ to refresh hair between washes.

How often can I reapply HeatBounce?

Apply HeatBounce every time before you apply heat, including if you switch between blow drying to hot tools.

the future of heat protection

less breakage after blow drying⁷

degree heat protection from cuticle¹ to cortex²

heat protect + condition in one step

how to use HeatBounce

1. Apply throughout sectioned hair, brushing through to help with even distribution.

2. Less is more. Start small and build as needed. Hair should feel soft and tangle-free, but not coated.

3. Use on towel-dried hair before blow drying and on dry hair before hot tools.

learn more on our blog

how to use HeatBounce conditioning heat protectant

See how K18 unlocks our community's expression

4.8

Rated 4.8 out of 5 stars

Based on 375 reviews

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375 reviews

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Sarah R.
Verified Buyer
Reviewing
HeatBounce conditioning heat protectant 4oz
I recommend this product
Age 35 - 44
Client Hair Concerns Heat Damage, Frizz, Fragile/Brittle Hair, Split Ends, Oily hair/scalp
Client Hair Types Fine/Thin, Straight/Wavy
Client Results Less Frizz, Cleaner, fresher hair, Oil absorbed, Bouncy Hair, Visible Difference
Rated 5 out of 5 stars
1 hour ago
Awesome protectant!
I’ve tried a fair share of different heat protectants. This one takes the cake! No overwhelming smell, doesn’t weigh down my fine hair, and protects against all of my heat tools. Love it!!! I’ll be recommending this to everyone! ❤️
Was this helpful?
Brenda M.
Verified Buyer
Reviewing
HeatBounce conditioning heat protectant 4oz
I recommend this product
Age 55 - 64
Hair Concern Color-care, Fragile/brittle hair
Hair Type Fine/Thin
My Results Visible Difference
Rated 5 out of 5 stars
1 week ago
Heat bounce
See difference in my bar already
Was this helpful?
K
K18Hair
1 week ago
Brenda, we're so excited to hear that you're already seeing a difference with HeatBounce! It's amazing how quickly it can start working to protect and condition your hair. Thank you for the fantastic 5-star review! ✨
martha
Reviewing
HeatBounce conditioning heat protectant 4oz
I recommend this product
Age 25 - 34
Hair Concern Heat damage, Fragile/brittle hair
Hair Type Fine/Thin
My Results Less Breakage
Rated 5 out of 5 stars
1 week ago
love it
recommend it to al my thin hair girlies, this heat protectant spray gives you everything you need without weighting down hair or making it look or feel greasy, a must have for sure, a few sprays is all you need since it sprays nicely
Was this helpful?
K
K18Hair
1 week ago
Martha, we're absolutely thrilled to hear that HeatBounce is perfect for your thin hair! It's amazing that you're experiencing all the protection and conditioning benefits without any of that heavy, greasy feeling.
Amanda A.
Verified Reviewer
Reviewing
HeatBounce conditioning heat protectant 4oz
I recommend this product
Age 35 - 44
Hair Concern Heat damage, Frizz, Fragile/brittle hair, Dryness
Hair Type Curly/Coily, Thick/Coarse
My Results Soft Touchable Hair, Smoother Hair, Visible Difference, Bouncy Hair
Rated 5 out of 5 stars
1 week ago
Awesome!
*I was gifted this product from K18 to review. My opinions are my own*
My thick curly hair can sometimes be an issue for me personally to manage daily. So, I prefer to straighten my hair to better maintain it. Products I've used in the past never gave me the results I was hoping to achieve. It was always disappointing for me. This heat protectant spray from K18 has been amazing for my hair so far. My hair feels soft and it has a nice, lightweight bounce to it. It gives my hair moisture and it's easy to run my fingers through. The great protection I get from this, when using my flat iron, is something that I haven't experienced from previous products. The product also smells great and the texture makes it very easy to apply to my hair each time. I definitely recommend
Was this helpful?
K
K18Hair
1 week ago
It's wonderful that you're finally getting the results you've been hoping for - the soft feel, lightweight bounce, and moisture are exactly what we love to hear about. Thank you for sharing your honest review and for recommending it to others!
Jennifer N. H.
Reviewing
HeatBounce conditioning heat protectant 4oz
I recommend this product
Age 45 - 54
Hair Concern Frizz, Extending time between washes, Split-Ends, Heat damage
Hair Type Curly/Coily
My Results Less Frizz, Bouncy Hair, Visible Difference, Defined Curl/Wave Pattern, Soft Touchable Hair
Rated 5 out of 5 stars
2 weeks ago
Love it
I was gifted by the brand, I’m absolutely loving the new K18 Heatbounce conditioning heat protectant! It’s smells so good and works awesome! No frizz and no heat damage so definitely It’s a YES for me my hair has no frizz! I’m love this stuff, my hair has never been this soft and looks so good!
Was this helpful?
K
K18Hair
1 week ago
We're so thrilled to hear how much you're loving HeatBounce, Jennifer! It sounds like it's delivering everything we designed it for - amazing scent, frizz control, heat protection, and that incredible softness. Thank you for sharing your wonderful experience with us!

*Disclaimers

HeatBounce conditioning heat protectant

Description

Description

how to use HeatBounce conditioning heat protectant

Meet HeatBounce: Deeper Heat Protection Than Ever Before*

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