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K18 HeatBounce conditioning heat protectant bottle on a pink background
K18 leave-in conditioner bottle with promotional text on a colorful background
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.
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.
4.8
Rated 4.8 out of 5 stars
543 Reviews
bestseller

HeatBounce conditioning heat protectant

The future of heat protection

Size:
4oz
Regular price $48
Regular price $0 Sale price $48
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Color:
4oz

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K18 HeatBounce conditioning heat protectant bottle on a pink background

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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
full-size leave-in molecular repair hair mask
FutureIQ™ biomimetic hair longevity serum
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K18 HeatBounce conditioning heat protectant bottle on a pink background
K18 leave-in conditioner bottle with promotional text on a colorful background
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.
K18 HeatBounce conditioning heat protectant bottle on a pink background
K18 leave-in conditioner bottle with promotional text on a colorful background
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.
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
85%
less breakage after blow drying⁷
450
degree heat protection from cuticle¹ to cortex²
Powered by resilicore™

Inspired by proteins in nature that can withstand extreme temperatures.

Explore the Science 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
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Powered by new patented heat-shielding tech.
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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 543 reviews
97%would recommend these products
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.
Customers Talked About
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543 reviews
  • Cara R.
    Verified Buyer
    Reviewing
    HeatBounce conditioning heat protectant 4oz
    I recommend this product
    Age 35 - 44
    Hair Concern Heat damage, Fragile/brittle hair, Split-Ends, Dryness
    Hair Type Thick/Coarse
    My Results Visible Difference, Less Breakage, Smoother Hair
    Rated 5 out of 5 stars
    1 hour ago
    Amazing

    I love this spray! My friend recommended because I have been dealing with breakage and this and the leave in treatment is working great!

    Was this helpful?
    K Profile picture for K18Hair
    K18Hair
    19 minutes ago

    Thank you so much for the 5-star review, Cara! We're thrilled HeatBounce is working great for you! 💙 We appreciate your support! ✨

  • Nicole E.
    Verified Buyer
    Reviewing
    HeatBounce 1.6 oz
    I recommend this product
    Age 35 - 44
    Hair Concern Heat damage, Frizz, Dryness
    Hair Type Straight/Wavy, Thick/Coarse, Fine/Thin
    My Results Less Frizz, Visible Difference, Smoother Hair, Soft Touchable Hair, Cleaner, fresher hair
    Rated 5 out of 5 stars
    Yesterday
    Best Heat Protectant

    Purchased this on a whim and I do not regret it. My hair feels so soft and smooth after using this. I have bleached dry hair and I swear this adds life back into it. Doesn't hurt that it also smells great.

    Was this helpful?
    K Profile picture for K18Hair
    K18Hair
    Yesterday

    Thank you so much for the love! 💙 We're thrilled to hear you're loving HeatBounce and that it's bringing life back to your hair! ✨

  • Christine H.
    Verified Buyer
    Reviewing
    HeatBounce conditioning heat protectant 4oz
    I recommend this product
    Age 55 - 64
    Hair Concern Chemical damage, Heat damage, Fragile/brittle hair, Dryness, Split-Ends
    Hair Type Fine/Thin
    My Results Less Frizz, Visible Difference, Less Breakage, Smoother Hair, Soft Touchable Hair
    Rated 5 out of 5 stars
    Yesterday
    Amazing

    Exactly what I needed! Smells great and makes my hair smooth, less frizz and heat damage!

    Was this helpful?
    K Profile picture for K18Hair
    K18Hair
    Yesterday

    Thank you so much for the 5-star review, Christine! We're thrilled to hear you're loving HeatBounce! 💙 We appreciate your support! ✨

  • Julie B.
    Verified Buyer
    Reviewing
    HeatBounce conditioning heat protectant 4oz
    I recommend this product
    Age 65+
    Hair Concern Color-care, Frizz, Chemical damage, Dryness
    Hair Type Fine/Thin
    My Results Smoother Hair, Visible Difference, Less Frizz, Less Breakage, Soft Touchable Hair
    Rated 5 out of 5 stars
    Yesterday
    HeatBounce

    Really helps with tangles. Leaves your hair feeling soft and helps with frizz

    Was this helpful?
    K Profile picture for K18Hair
    K18Hair
    Yesterday

    Thank you so much for the love! 💙 We're thrilled to hear HeatBounce is helping with tangles and frizz while keeping your hair feeling soft! ✨

  • Christy J.
    Verified Buyer
    Reviewing
    HeatBounce 1.6 oz
    I recommend this product
    Age 45 - 54
    Hair Concern Frizz, Fragile/brittle hair, Split-Ends, Heat damage, Dryness
    Hair Type Fine/Thin, Grey Hair, Medium Density, Straight/Wavy, Thick/Coarse
    My Results Less Frizz, Bouncy Hair, Less Breakage, Smoother Hair, Shinier Hair
    Rated 5 out of 5 stars
    2 days ago
    Let’s Bounce

    This has been great for my clients who want volume but movement as well.

    Was this helpful?
    K Profile picture for K18Hair
    K18Hair
    2 days ago

    Thank you so much for the love! 💙 We're thrilled to hear HeatBounce is delivering the volume and movement your clients are looking for! ✨

*Disclaimers

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