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K18 Leave-In Molecular Repair Mask 50ml
NZD $135.90
or 6 weekly interest-free payments from NZD $22.65 with 
what's this?
4-minute leave-in treatment to reverse damage.
Hair like new. This leave-in mask heals and strengthens hair with lightweight moisturizing benefits to detangle and keep hair smooth and soft, without weighing it down. Please see dosage chart for exact usage. For best results, use for the first 4-6 consecutive washes following a service, and then every 3-4 washes as needed to maintain hair strength.
Use
Description
Use:
- Shampoo, do not condition. Towel dry thoroughly.
- Begin with 1 pump of K18 Mask and add more as needed depending on the length, thickness, and condition. Work evenly into hair, one pump at a time, from ends to roots.
- Let sit for 4 minutes to activate.
- Do NOT rinse out. Style as usual.
Best for: All hair types.
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Real Professional Care & Advice
Jo Knight (verified owner) –
Shannon Lee (verified owner) –
Amazing product, I am so glad I purchased this, it’s saved my hair and I’ve already seen a huge improvement! And it makes it feel amazing so that’s a bonus!
Kelly (verified owner) –
So easy to use (great for a busy mum!) and noticeably different hair after first treatment. Would definitely recommend
Karla H. (verified owner) –
In love with this product! My hair feels amazing. Awesome service and fast postage too, thank you so much 🤩
Raye (verified owner) –
Recommended to me by a fellow frizzie haired friend. Have spent thousands on salon treatments & straightening products. This stuff is incredible & does just what they claim it does. Haven’t looked back since.
LIZ (verified owner) –
Fantastic product. Blonde hair never shines now my hair has shine. Pricey but well worth every cent highly recommend
Jessica G. (verified owner) –
I have used twice and can notice a difference already. Great service from Synergy and fast shipping
Aimee (verified owner) –
A product that really works!
Rikki-Lee Howard-Cagabcab (verified owner) –
This saved my hairs life I have been using this product after damaging by my hair and I used this every time I washed my hair and the results are mind blowing
Rachel T. (verified owner) –
Highly recommend this stuff! I’ve used it 4 times so far and my hair looks and feels AMAZING!
Hannah (verified owner) –
Unbelievable! I never leave reviews because I am ultimately lazy but I couldn’t let this go without saying something. This product is actually incredible, my hair feels like silk and it looks like I’ve just had a hair cut. I’ve never ever experienced a product that worked so well. I’m in for life.
Sylvie W. (verified owner) –
Amazing after one use I can really see the difference. I read reviews before buying as it’s pricey but so worth the investment in your hair ♥️♥️♥️
Ingrid Dukker (verified owner) –
Charlotte Anderson (verified owner) –
Even after the first use of this my hair felt so much better, so much softer and sat so nice naturally. Highly recommend!
Anonymous (verified owner) –
Amazing product! Synergy; great company to buy from- thank you!
Jessica G. (verified owner) –
As a bleach blonde this stuff is a lifesaver. Repeat buyer and will be buying again.
Sarah (verified owner) –
Due to a dying and stripping accident, my hair was extremely chemically damaged and it was going to have to be all cut off. After purchasing this product, my long hair is back to a healthy looking condition (about 90% better). This is my third bottle which will take it back and beyond what it was. As pricey as it is, it was worth it.
Michelle C. (verified owner) –
Brilliant stuff, it has totally rescued my hair… highly recommend
Teri T. (verified owner) –
My hair should be looking like a clown with how thin it it and how many times I have bleached, chemically straightened it and generally dyeing with colors. This product helps with the damage and make it become as healthy as possible. I will continue buying! ❤️
Anonymous (verified owner) –
Amazing. Repaired my super damaged hair very quickly. I’d tried Kerastase Resistance and Olaplex previously, and for a long time … they don’t even come close to the repair I got from K18
Lisa Wilson (verified owner) –
My daughter 13 and is a swimmer with super curly hair. This product is the best for her hair to prevent damage and help keep the curl banging!
Keiren (verified owner) –
Amazing product. I can definitely feel the difference in my hair after using it.
Anonymous (verified owner) –
Excellent product. Product arrived within two days, wow. Thank you for the extremely fast service.
Sandy (verified owner) –
The first time I used K18 I noticed a significant difference.
My hair is coarse, dry and brittle this product is like magic! I’ve spent $1000’s on haircare products promising ‘amazing results’ but not for me, however K18 is working for me! I love it and how it’s healing my hair to be healthy!!
Sophie (verified owner) –
Amazing , noticable diffrence in my over processed hair.Hair instantly feels better an naturally dries well.10/10
Doris (verified owner) –
The best product I have ever tried (and the dearest)!!!! I guess you get what you pay for!!! 🥰
Michelle (verified owner) –
Excellent product
Jessica Garing (verified owner) –
This is my holy grail product. I will continue to purchase its saved my bleach blonde hair
Katie Holmes (verified owner) –
Purchase was so easy and came in the mail super fast!!!
Kerstine V. (verified owner) –
Pricey but so worth it.
I only use a pump for my hair. I have used it 6x and have seen noticeable results already
Anonymous (verified owner) –
Amazing product. I’d have given up on being blonde by now if not for this. It’s easy to use and has repaired incredibly damaged bleached hair to the point where it actually feels like healthy hair again.
Morgan M. (verified owner) –
I love how quick it is to use, just pop it in post shower no need to rinse! It’s done wonders for my bleach damaged hair.
Jackie Sanders (verified owner) –
In general I find synergy amazing. Hence the 5 stars.
Unfortunately the k18 I received had a broken pump. Which I know is not synergy’s fault. I could have returned it, but I kept it as wanted the product. Had to pry it open.
Georgia Langridge (verified owner) –
Sharni (verified owner) –
This product is amazing!
Selena D. (verified owner) –
Had been wanting this product for so long! Was processed quickly after ordering and received updates along the way. Definitely my new go to website for ordering products.
Nicky (verified owner) –
Frances (verified owner) –
Such a good product! Expensive, yes, but my thick wavy, dyed (I’m 67 so naturally grey) hair is left soft and shiny and feels young again!
Anonymous (verified owner) –
Seems to be working well on my bleached hair
Jude Houghton (verified owner) –
Great product
Jacqueline Sanders (verified owner) –
K18 is amazing. Synergyhair as always amazing . Fast delivery
My no 1 hair care place
Doreen (verified owner) –
Works so well!
Anonymous (verified owner) –
Crystal Tuhaka (verified owner) –
All the top colorists in the world use K18 which is why I bought it and they are right!!! It’s well worth it!!!
Elyana –
my hair type is oily on the root side and very dry on the end side and can be very hard to manage and frizzy. After bleach and got my hair coloured, the texture of my hair was worst! It was dry and no matter how many treatment products I use.. it didnt work.. I almost gave up on my hair and thought tho just cut it short.. but then I saw a lady on the YouTube channel sharing how K18 has improved her hair. Was very skeptical but I purchased it anyway and wow.. my hair felt like it is reborn. It is now shiny, it shows its own wave.. and I don’t need too many products after I have this product. Just the shampoo and this mask. My hair is now bouncy and shiny and I can’t believe how good my hair looks now. Thank you to the scientists who developed this formula for the past 10 years.. I feel confident flashing my dyed hair now.. its pricey.. but well worth it.
Anonymous (verified owner) –
It works wonders, second treatment now 🙂
Hayden (verified owner) –
Maria-Antonieta Diaz-Ruiz (verified owner) –
Amazing product. You can see results in the first application
Jacqueline (verified owner) –
After one use it lived up to the hype already. I have wavy bleached hair that was SUFFERING in the NZ humidity. After one use my split ends are drastically improved, frizz decreased, hair is smoother and shinier. My goodness she (K18) was pricey but so is getting your hair done in NZ and I’d say K18 would save me a trip or three to the hairdresser thus justifying the price tag. If I had to choose K18 or Olaplex, K18 would have it. Stay tuned for what it will do after 2 uses
Suzanne (verified owner) –
Awesome product, Hair felt amazing after 1st use.
Gemma R. (verified owner) –
fabulous treatment – really helps my hair
Lisa Watson (verified owner) –
Awesome service arrived the next day!
georgie (verified owner) –
used olaplex for years … but this is next level! such a big difference in health and thickness of my bleach blonde ruined hair in three months (it had previously snapped off to a mullet above my shoulders) andres s now mid back and full of life
Anonymous (verified owner) –
Love it definitely recommend this product really helped repair my dry damaged hair
Anonymous (verified owner) –
My dry curly hair was instantly revived
Cristina S. (verified owner) –
Amazing what this product can do! My hair is heavily bleached and the results after one use are crazy!
Janine Bryce (verified owner) –
YOU NEED THIS. If you have any kind of damage, from styling to colouring to anything. I know, it’s seems like a huge amount to spend on such a little bottle, but it really does go a loooong way. Reading in the instructions about not conditioning and thinking about how much conditioner my fine wavy hair eats, I thought that it would last one application, but you only need a few mls and it’s ridiculously easy. GET THIS!!!!
Kate (verified owner) –
Haven’t used this for long enough to speak with much authority, but… I’m hoping it restores my hairs health at some point! Not sure if it’s worth the price as yet, but maybe…?
Michelle (verified owner) –
Great product
Cam (verified owner) –
Makes my hair really soft and manageable
Jacqueline Sanders (verified owner) –
As always synergy u rock .wouldn’t go anywhere else
Maria-Antonieta (verified owner) –
What an amazing product. You’ll see results from first application.
Brigid Kissick (verified owner) –
Laura (verified owner) –
My hair is quite damaged and dry and already noticed a significant difference after one use
Alexis Watson (verified owner) –
Brandy (verified owner) –
Really liking the feeling of this, noticed how soft my hair has gotten and my breakage has softened so its not as obvious. Look forward to seeing more results 🙌
Saskia v. (verified owner) –
Karen (verified owner) –
My hairdresser has started using this on her clients and was telling me the science behind it. Decided to purchase and have not been disappointed.
Virginia (verified owner) –
Both my daughter and I were really happy with the results from this product; our hair looks so much healthier! I have just purchased our second bottle.
Maria-Antonieta (verified owner) –
The best product to repair your hair ever
Anonymous (verified owner) –
Jacqueline Sanders (verified owner) –
See my previous review. K18, great stuff.
Synergy you rock.x
Mel Z. (verified owner) –
I have only used it once so far but my hair feels smoother and stronger. Definitely glad I brought this
Shirley (verified owner) –
Have used this product x2 and my hair feeling a lot softer fingers crossed after recommended 6 uses will be worth the high price
Veronica C. (verified owner) –
I keep re-purchasing it does make my hair stronger.
Anonymous (verified owner) –
Really love this. Is helping with my damaged hair
Lisa Wilson (verified owner) –
My daughter is 14 and a swimmer. This product works wonders on her super curly hair. I use it when I feel like my hair could use some love, but I find I don’t need it often now that I have restored my hair.
Alex (verified owner) –
I’ve been using this product for months now and its amazing! Highly recommended for damaged, broken hair!
Jacqueline Sanders (verified owner) –
Synergy rocks. As usual, product arrived in 24 hours and was exactly what I ordered
Leonie (verified owner) –
An absolute game changer…wouldn’t use anything else now. Brings my foiled blonde hair back to life so it is now soft and shiny.
Jacqueline Sanders (verified owner) –
As usual, synergy is an amazing company to deal with. You guys rock. And product is always A+
Pete (verified owner) –
Purchased as a gift for my wife – she loves it!
Stephanie (verified owner) –
Seems pretty good so far , I’m looking forward to seeing how my hair is once I’ve finished the bottle
Rachel Healy (verified owner) –
Rose (verified owner) –
Worth every dollar spent. Already started seeing results after the 2nd use. My hair has less frizz and feels so healthy. Will buy again.
Anonymous (verified owner) –
Sonia (verified owner) –
Seems to do what it says it will, if you follow the instructions for use. Not a miracle instant fix but does help.
Brandy P. (verified owner) –
Emma W. (verified owner) –
Amazing product, has helped repair my hair after my hairdresser destroyed it. My hair is shiny and smooth again and feels healthier.
Super quick shipping too, which is always appreciated.
Kirstie (verified owner) –
This is an absolute must if you have bleached hair, scraggy hair, birds nest… whatever! It works if used as directed ie don’t use too many pumps, follow the guidelines
Anonymous (verified owner) –
Char (verified owner) –
I adore this! Has saved my bleached hair so that I can put more bright pink in, I sweat by k18
Anonymous (verified owner) –
Jessica Garing (verified owner) –
Anonymous (verified owner) –
Haven’t seen results so far as have only used a couple of times but makes hair feel pretty soft.