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.

Person with long hair using a pink comb against a pink background with text about hair care.

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.

Four women using a hair styling tool with text indicating different styles you can do with heatbounce.

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

451 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 (451 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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Rated 4.6 out of 5 stars

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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

Inspired by proteins in nature that can withstand extreme temperatures.

EXPLORE THE SCIENCE

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

Blow dry, curl + straighten your hair—without damage.

Meet HeatBounce: Deeper Heat Protection Than Ever Before*

What Hot Tools Are Really Doing to Your Hair

If your routine involves heat—this one's for you.

feel what's possible with K18

See how K18 unlocks our community's expression

4.8

Rated 4.8 out of 5 stars

Based on 451 reviews

Reviews Summary

Customers say this heat protectant leaves hair silky and smooth while styling. Many reviews highlight its lightweight formula that doesn't weigh hair down. The spray effectively detangles and adds shine without feeling greasy. Users with fine, curly, and color-treated hair appreciate its versatility. Common feedback mentions the pleasant scent and easy application. While most find it perfect for daily use, some note that a light application works best, especially for fine hair.

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451 reviews

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Cecilia D.
Verified Buyer
Reviewing
HeatBounce conditioning heat protectant 4oz
I recommend this product
Age 55 - 64
Hair Concern Heat damage, Dryness, Extending time between washes, Split-Ends, Color-care
Hair Type Medium Density, Grey Hair
My Results Stronger Hair, Less Breakage, Visible Difference, Smoother Hair, Cleaner, fresher hair
Rated 5 out of 5 stars
3 days ago
Love HeatBounce
I tried multiple heat proctectants and Heat Bounce by far is the best product out there! My daughter was at my house for Thanksgiving and tried it and put it on her Christmas wish list. The smell is really good too and my hair is so soft after using it!
Was this helpful?
K
K18Hair
22 hours ago
Thank you so much for your incredible review, Cecilia! We're absolutely thrilled to hear that HeatBounce has become your go-to heat protectant after trying so many others - there's no better compliment than knowing our formula is delivering that perfect protection while leaving your hair feeling so soft!
Angela A.
Verified Buyer
Reviewing
HeatBounce conditioning heat protectant 4oz
I recommend this product
Age 45 - 54
Hair Concern Chemical damage, Heat damage, Frizz, Dryness, Split-Ends
Hair Type Fine/Thin, Straight/Wavy, Grey Hair
My Results Less Frizz, Bouncy Hair, Visible Difference, Stronger Hair, Less Breakage
Rated 5 out of 5 stars
1 week ago
Damage prevention
This product will do wonders for your hair if you heat style your hair. It also doubles as a wonderful bouncy conditioner
Was this helpful?
K
K18Hair
6 days ago
Thank you so much for your incredible review, Angela! We're absolutely thrilled to hear that the HeatBounce conditioning heat protectant is working wonders for your heat-styled hair and that you're loving how it doubles as a bouncy conditioner - there's nothing better than knowing this dual-action formula is providing both the protection and conditioning your hair needs! ❤️
Kim S.
Verified Buyer
Reviewing
HeatBounce conditioning heat protectant 4oz
I recommend this product
Age 35 - 44
Hair Concern Heat damage, Fragile/brittle hair, Dryness
Hair Type Fine/Thin
My Results Smoother Hair, Shinier Hair, Soft Touchable Hair
Rated 5 out of 5 stars
3 weeks ago
Amazing
I love how this smells and there is no weird residue. My hair feels super soft.
Was this helpful?
K
K18Hair
1 week ago
Thank you so much for your amazing review, Kim! We're absolutely thrilled to hear that you love the HeatBounce conditioning heat protectant - it's wonderful that you're experiencing that incredible softness while enjoying the beautiful scent, and we're so glad there's no weird residue left behind, just perfectly protected and conditioned hair!
Maria G.
Verified Buyer
Reviewing
HeatBounce conditioning heat protectant 4oz
I recommend this product
Age 55 - 64
Hair Concern Chemical damage, Heat damage, Color-care, Frizz, Fragile/brittle hair
Hair Type Medium Density, Grey Hair
My Results Less Frizz, Bouncy Hair, Visible Difference, Stronger Hair, Shinier Hair
Rated 5 out of 5 stars
1 month ago
A must have.
My daughter uses this product and her hair is lovely. I decided to give it a try. It's amazing. My hair looks healthier and no freeze.
Was this helpful?
K
K18Hair
1 week ago
Thank you so much for your wonderful review, Maria! We're thrilled to hear that both you and your daughter are loving the HeatBounce conditioning heat protectant and that it's making your hair look so much healthier with no frizz - it's amazing how this heat protectant formula can give you that smooth, protected look while keeping your hair nourished!
Diana M.
Verified Buyer
Reviewing
HeatBounce conditioning heat protectant 4oz
I recommend this product
Age 25 - 34
Client Hair Concerns Heat Damage, Color Care, Chemical Damage, Split Ends, Dryness
Client Hair Types Fine/Thin
Client Results Stronger hair, Visible Difference, Less Breakage, Soft Touchable Hair, Smoother Hair
Rated 5 out of 5 stars
1 month ago
El mejor protector de calor
El mejor protector de calor que he probado, me gusta mucho que ayuda a desenredar el cabello y tiene un aroma muy agradable. Soy estilista profesional de bellami y lo recomiendo a todas mis clientas, es excelente para usar en extensiones.
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K
K18Hair
1 month ago
¡Muchísimas gracias por tu increíble reseña, Diana! Nos emociona saber que el HeatBounce es el mejor protector de calor que has probado y que te encanta cómo ayuda a desenredar el cabello con ese aroma tan agradable.

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HeatBounce conditioning heat protectant

Description

Description

how to use HeatBounce conditioning heat protectant

Meet HeatBounce: Deeper Heat Protection Than Ever Before*

What Hot Tools Are Really Doing to Your Hair