Sarah K So Liss Step 2 Expert Tech Progressive Keratin and Protein System - 1000ml

Formaldehyde-free keratin treatment | Smooth and hydrated finish | Professional long-lasting frizz control

Overview

The Sarah K So Liss Step 2 Expert Tech Progressive Brush is a formaldehyde-free keratin treatment designed to deliver smooth, frizz-free, and hydrated hair. Infused with whey protein and keratin, its advanced formula enhances shine and softness throughout the straightening process, leaving hair silky, manageable, and healthy-looking.

What It Does

Straightens and smooths unruly, curly, or frizzy hair
Provides deep hydration while maintaining softness and shine
Strengthens the hair fiber for resilience against breakage
Controls frizz and reduces unwanted volume
Delivers professional salon results with lasting smoothness

Key Ingredients

Whey Protein - Nourishes, reduces frizz, and helps preserve hair strands
Keratin - Reconstructs the inner strand structure for strength and smoothness
Shea Butter - Provides moisture and softness
Macadamia & Coconut Oils - Add shine, conditioning, and flexibility
Hydrolyzed Collagen - Improves elasticity and resilience

Who It Is For

Recommended for:

Curly, wavy, or frizzy hair (Types 2A–4C)
Clients seeking long-lasting smoothness without harsh chemicals
Thick, resistant, or high-volume hair prone to frizz
Color-treated or chemically processed hair needing reconstruction
Salon professionals requiring consistent and safe keratin performance

How to Use

Wash hair with So Liss Step 1 Deep Clean Shampoo. Leave on for 3 minutes during the last wash. Rinse thoroughly.
Dry completely. Divide hair into 4 sections.
Apply Step 2 evenly from root to tips, strand by strand. Comb through to distribute.
Leave on for 40 minutes. Rinse thoroughly with lukewarm or cold water for 5 minutes.
Apply Neutralizing Mask SK (for dark hair) or Neutralizing Blonde Mask SK (for blonde hair). Leave 5–15 minutes, then rinse.
Blow-dry and straighten in thin sections at 190–230°C, 7–10 passes per strand. Focus more on roots and less on ends.

Pro Tip: Always perform a strand test before full application. Use protective gloves, maintain ventilation, and adjust flat iron temperature according to hair sensitivity.

Complete Your Routine

So Liss Step 1 Deep Clean Shampoo - Essential pre-treatment cleansing

Main Benefits

Formaldehyde-free professional straightening system
Lasting smoothness with shine and hydration
Strengthens and reconstructs hair from within
Reduces frizz and improves manageability
Salon-size 1000ml for multiple applications

FAQ: Progressive Keratin Treatments

What is the difference between progressive and regular keratin?

Regular keratin treatments deliver instant results but usually last around 3 months. Some require waiting 48–72 hours before washing and may flatten natural volume.
Progressive keratin treatments build results gradually with each session, allowing hair to remain smoother, shinier, and more manageable over time. They usually last 4–6 months and often allow same-day washing.

How often should progressive keratin be applied?

On average, every 4–6 months depending on hair texture and maintenance routine.
Thick or resistant hair may need reapplication after 3–4 months, while finer hair may last longer than 6 months.
Results last longer with sulfate-free shampoos, keratin-safe conditioners, and proper aftercare.

Summary

The Sarah K So Liss Step 2 Expert Tech Progressive System is a professional keratin treatment that ensures smooth, frizz-free, and luminous hair without formaldehyde. Enriched with whey protein, keratin, and nourishing oils, it hydrates while strengthening the fiber. Perfect for stylists delivering safe, effective, and long-lasting straightening results.

Size: 1000ml (33.8 fl oz)