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L'Oreal Professionnel

L'Oreal Professionnel Serie Expert Keratin Alpha Sleek Hair Serum 50ml
£22.80
RRP £28.50 (20% off)
Spend £25.00 more for FREE standard UK delivery.

Hair Type Concern

Dry, Damaged, Frizzy

  • Rated Excellent
  • Free UK delivery over £25
  • Order by 10pm for next day delivery*
  • 100% authentic products
  • Free UK next day delivery over £80

Product Description

L'Oreal Professionnel Serie Expert Keratin Alpha Sleek Hair Serum (50ml) is a professional finishing serum designed to smooth, seal and protect the hair fibre while controlling frizz and unwanted volume.

Formulated with 5% Keratin Sealer, the mirror-shine serum seals the hair's keratin structure, leaving strands visibly smoother, shinier and easier to style, and as part of the Alpha Sleek routine it helps reprogram hair for up to 2 weeks of frizz control. The heat-activated formula defends against up to 80% humidity and heat damage of up to 230°C, leaving hair glossy, controlled and polished without heaviness. Artificial colourant-free and alcohol-free.

Key Benefits

  • Mirror-shine finishing serum for frizz-prone hair.
  • 5% Keratin Sealer seals the keratin structure.
  • Protects against up to 80% humidity.
  • Heat protection up to 230°C.
  • Instant shine that can last up to 5 days.

Key Ingredients

  • 5% Keratin Sealer, which seals and smooths the hair's keratin structure.

How To Use
  • Apply a small amount evenly through lengths and ends of damp hair.
  • Blow-dry to activate the smoothing effect.
  • For longer-lasting results, use a straightening iron after drying.
  • Use as part of the Keratin Alpha Sleek routine.

Ingredients & Product Highlights

The list of ingredients is subject to change, it is recommended to review the ingredient list printed on the packaging of the product prior to usage or consumption. If the ingredient list doesn't load below, please email our customer care team and we'll send an image of the packaging.

Delivery & Returns

Justmylook offers free delivery on all UK orders over £25 via Royal Mail 48 Tracked. We offer free next-day delivery on all orders over £80 via Royal Mail 24 Tracked.

Royal Mail 24 is the only service that will be dispatched for next day delivery on a Sunday.

Last Order Dates for Christmas: 
Royal Mail Special Delivery: Order before 2:00pm on 23/12/26 for delivery by 24/12/26.
Royal Mail 24 Tracked: Order before 9:00pm on 22/12/26 for delivery by 24/12/26.
Royal Mail 48 Tracked: Order before 10:00pm on 20/12/26 for delivery by 24/12/26.

We’ve extended our returns period this Christmas to give you complete peace of mind for any gifts purchased from Justmylook during the festive season. Any items purchased between 2nd November 2026 and 23rd December 2026 can be returned up until 12th January 2027. All goods must be returned in their original, sealed packaging and be in a re-saleable condition. In the interest of hygiene, we are unable to accept returns on unwanted items that have been used and have had their security and/or hygiene tags removed. Items purchased after 24th December 2026 will be subject to our standard returns policy.

To see our returns policy, please click here.

We have a variety of express services available. 

Royal Mail 48 Tracked: Orders placed before 6:00 pm are dispatched the same day Mon-Fri, and 2:00 pm Sat. Orders after this threshold will be dispatched the next working day. Delivery takes 2 days, including Saturdays. This service is free for orders over £25, orders under £25 will be subject to a £2.99 delivery charge.

Royal Mail 24 Tracked: Orders placed before 10:00 pm Mon-Fri, before 2pm Saturday and before 12pm Sunday are dispatched the same day. Orders after this threshold will be dispatched the next working day. Delivery will take place the next day, including Saturdays & Sundays. This service is free for orders over £80. The charge for this service is £1.99 for orders between £25.00 - £79.99, and £3.99 for orders under £25.

Royal Mail Special Delivery: Orders placed before 2:00 pm are dispatched the same day Mon-Fri. Orders after this threshold will be dispatched the next working day. Delivery will take place the next day, including Saturdays. The charge for this service is £5.99.

DPD: Orders placed before 2:00 pm are dispatched the same day Mon-Fri. Orders after this threshold will be dispatched the next working day. Delivery will take place the next working day. The fee for this service is £5.99.

Republic of Ireland: We're sorry to inform our customers in Ireland
that we have suspended shipping to the Republic of Ireland. Recent changes to
legislation have made it impractical for us to continue offering reliable,
cost-effective delivery to Irish addresses. We don't want our customers facing
unexpected charges or delays at the border, so we've taken the decision to
pause Irish deliveries until further notice.

*  Next day delivery offered before 10pm,  Monday - Friday.

Please note it is not currently possible to offer a next-day delivery service to the below postcodes for orders placed after 5:00 pm. AB, BT, DD, DG5-9 & 10-16, FK17-21, G58, G60, G62, G63, G65, G71-84, GY, HS, IM, IV, JE, KA, KW, KY10, KY14-16, ML10-12, PA20-38, PA41-49, PA60-78, PH, PO30-41, TD, TR21-25, ZE.

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