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K18's Hair Treatment Reviews

Honest Review: Is K18's Repair Hair Mask The Next Olaplex

What is K18 Hair Treatment?

K18, formerly known as KhairPep and one of the latest products in hair bonding technology, is a reparative leave-in treatment that claims to reverse hair damage from lightening and chemical services, mechanical damage and heat, bringing hair back to its youthful state.

K18's repair hair treatment


You may have seen the bottles, simple in design but adorned with a trademark strand of molecules, perched on the shelves of celebrity colourists in shared Instagram shots. The brand is spreading through the industry's most trusted professionals like a rumor, and with good reason: biomimetics, or essentially manually replicating a process found in nature. Through that framework, K18's line of products—particularly its celebrated Leave-In Molecular Repair Mask ($75)—actively repair damaged hair, collecting plenty of diehard fans in its wake.

The K18 Leave-In Molecular Repair Hair Mask is an award-winning haircare product—it’s been compared to (and is purportedly more effective than) the industry standard, Olaplex’s No. 8 hair mask. K18’s hair mask has even been hailed as a replacement for conditioner. Does it actually work?

Directions: Before the first use, wash with a clarifying shampoo. Shampoo hair; do not condition. Towel dry hair. Start with one pump and add more as needed depending on length and thickness. Work evenly through hair from roots to ends. Let sit 4 minutes. Do not rinse. Add styling products if desired and style as usual. Use for 4 to 6 consecutive washes and then every 3 to 4 washes for maintenance.

Is the K18 Leave-In Hair Mask Really a Frizz-Eliminating Godsend? 

K18 hair treatment review

I have thick, straight, long hair, but I do very little to maintain it. My hair has a life of its own and I have accepted this. Generally, I wash my hair every other day then use a leave-in conditioner and hair oil. I rarely use hydrating treatments and have not used the K18 Peptide treatment before.

My hair has been dehydrated with the sun and heat damage of summer, so this was perfect timing to try K18. It was not time-consuming. I used it every time I washed my hair for two weeks, and used about 3-4 pumps each time because of my long hair. I thought using it every time I washed my hair might be overkill, but for how coarse my hair is, it works perfectly.

I was hesitant about not using conditioner and using K18 as a leave-in conditioner instead, but it made my hair feel significantly softer. I like how it is not heavy or does not change the weight of my hair. I still used my hair oil to control frizz, but my hair is naturally on the frizzier side. I saw real results in a short amount of time. I loved it and will continue using it! This size of the bottle is also perfect for traveling this summer.

Use coupon code WELCOME10 for 10% off your first order.


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