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Keratin Alpha Sleek Mirror Sleek Serum

Keratin Alpha Sleek Mirror Sleek Serum is rated 4.7 out of 5 by 46.
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1.69 oz.
#E4564700
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What It Is

A heat-activated leave-in serum that seals the hair's structure for up to 10 washes of smoothness, frizz control, and humidity protection.

What It Does

• Seals hair outer keratin structure for up to 10 washes*

• Anti-humidity up to 80% humidity in the air

• Heat protection up to 230C (450F)

• 6x smoother hair**

 

*leave-in serum vs. untreated hair

** system of shampoo, smooth transformer, and leave-on vs. before application

What Else You Need to Know

Formulated with 5% Keratin Sealer, this serum seals the hair structure for smoothness, frizz, and volume control that lasts up to 10 washes.

1. Shake well before use.

2. On washed, towel-dried hair, section hair into two parts.

3. Spray into your hand (start with 2–4 sprays for thin hair, 6–8 for thick hair) and distribute evenly from lengths to ends.

4. Do not rinse.

5. This product is heat-activated. Blow-dry completely.

6. For maximum long-lasting results, use a straightening iron after blow-drying.

DIMETHICONE • BIS-(MORPHOLINOMETHYL C1-4 DIALKOXYSILOXY) DIMETHICONE • BIS-CETEARYL AMODIMETHICONE • PARFUM / FRAGRANCE • LINALOOL • CITRONELLOL • GERANIOL

Purchases made in SalonCentric stores may be returned to any SalonCentric store. Purchases made through SalonCentric Customer Service, SalonCentric Business Partners, and SalonCentric.com orders Sold and Shipped by SalonCentric may be returned to a SalonCentric store; however, the return must not exceed $450 and must include the original receipt, packing slip, or invoice. For returns in-store of online orders, the refund will be credited back to the original payment method once the return has been processed. For SalonCentric.com Online Exclusive orders sold and shipped by third-party sellers, please see more details linked below for return steps.

The SalonCentric return policy does not currently apply to Kérastase & Shu Uemura purchases. Kérastase & Shu Uemura do not accept returns.

Click to see more details.

Rated 5 out of 5 by from Silky Smooth Expensive Hair Thank you L'Oreal for allowing me to sample the Keratin Alpha Sleek Mirror Sleek Serum in exchange for my honest review! The Mirror Sleek Serum should be utilized with the entire line as using it alone provides little to no improvement. When using the Mirror Sleek Serum with the entire system....it works wonders!! Turns frizzy unruly hair into silky smooth expensive hair!! The fresh clean scent lingers in hair even after styling!
Date published: 2026-06-15
Rated 4 out of 5 by from Great serum for shiny hair I used the serum after using the whole system shampoo mask, and treatment and it really does help control the frizz and leave my hair super soft and shiny. It takes very little bit of product to see the results.
Date published: 2026-06-14
Rated 4 out of 5 by from Worth trying I received this product from BzzAgent to review. I used this alone and noticed no difference in blowout. When used as a system hair felt noticeably smoother. I sprayed in my hand as directed..wish it was easier to apply/distribute. Scent is similar to mega sleek by matrix..
Date published: 2026-06-13
Rated 5 out of 5 by from Heat protection & shine I was really impressed with this serum and the entire Keratin Alpha Sleek line overall. I have very coarse, frizzy, 2C textured hair, and I noticed an improvement almost immediately compared to the products I normally use in my routine. My hair felt noticeably softer, smoother, and shinier and even by day 4, I was waking up with significantly less frizz. I love that this is also a heat protectant! I absolutely loved the results! The liquid viscosity makes it excellent for fine hair as well as coarse hair.
Date published: 2026-06-13
Rated 5 out of 5 by from A little goes a long way. A little goes a long way! I use this serum AFTER my hair has already been dried and flat ironed as a last step to relieve frizz. You can use it on its own or as a whole system.
Date published: 2026-06-12
Rated 3 out of 5 by from Sleek, shiney This is a great product t and does help smooth the hair! However, use it cautiously it can make the hair seem greasy if you get too much but works great with the perfect amount! It does have a strong rose oil scent.
Date published: 2026-06-12
Rated 5 out of 5 by from Adds Shine Without Feeling Greasy This serum gives my hair a nice, healthy shine without making it look oily. I use a small amount on damp or dry hair, and it helps smooth out frizz and flyaways. My hair feels soft, looks sleek, and stays manageable throughout the day.
Date published: 2026-06-11
Rated 5 out of 5 by from Amazing! Smells nice, feels nice, leaves the hair looking and feeling amazing!
Date published: 2026-06-09
  • y_2026, m_6, d_18, h_12
  • bvseo_bulk, prod_bvrr, vn_bulk_3.0.46
  • cp_1, bvpage1
  • co_hasreviews, tv_3, tr_43
  • loc_en_US, sid_loreal-professionnel-keratin-alpha-sleek-mirror-serum, prod, sort_[SortEntry(order=SUBMISSION_TIME, direction=DESCENDING)]
  • clientName_saloncentric
  • bvseo_sdk, dw_cartridge, 17.1.0, p_sdk_3.2.0
  • CLOUD, getReviews, 6ms
  • reviews, product