The product packaging is missing the user instructions. Below are some instructions that I discovered on my own:

INSTRUCTIONS for the console, buttons from top to bottom.
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ELECTROTHERAPY: for improving the tone and appearance of the face:
Current intensity b0 to b9
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FLASHING: switching from light on to light off at specific time intervals
F1 steady light, F2-F4 flashing
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COLORS:
C0 off, C1 red, C2 green, C3 blue, C4 yellow, C5 purple, C6 cyan, C7 white, C8 alternating
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BRIGHTNESS A1 - A9 LED
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General information:
· Red light (630nm wavelength): It has been proven to enhance collagen production, reduce wrinkles and signs of aging, increase skin elasticity, tighten loose skin, rejuvenate cells, and improve blood circulation.
· Green light (520nm wavelength): Helps combat skin oiliness, regulates sebum production, and contributes to melanin balance.
· Blue light (470nm wavelength): Kills the propionic bacteria responsible for acne, reduces redness, scars, and inflammation.
· Yellow light (590nm wavelength): Helps collagen production. Reduces wrinkles, balances skin texture, reduces redness and inflammation. Stimulates the lymphatic system and helps make the skin soft and radiant.
· Purple light (390nm wavelength): Combines the benefits of red and blue light. Reduces wrinkles, fine lines, signs of aging, while also acting against inflammation, scars, and bacteria that cause acne.
· Cyan light (490nm wavelength): Balances skin texture, reduces broken capillaries on the face, and acts against inflammation and scars. Also treats sunburn.
· White light: Enhances the absorption of nutrients into the skin. Tightens loose skin, reduces fine lines, wrinkles, and skin discoloration, and reduces inflammation and scars.
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Personal experience:
* I am a 55-year-old man with no previous dermatological interventions on my face. My skincare routine was limited to daily use of sunscreen.
* First impressions: The device appears sturdy and well-made. The presence of multiple cables and the control console without user instructions make the initial use challenging.
* Usage: Electrotherapy, even at the lowest level, causes noticeable pain. After each treatment, I feel a tightening sensation in the skin, possibly a sign of rejuvenation.
* Results: After one week of daily use of the red light (10 minutes/day), I feel like my face has a sweeter appearance. This may be due to psychological projection.
* Reactions: I noticed a more positive reception from my environment, mainly from women. It may be due to a subconscious reaction to the improvement of my appearance.
* Scientific evidence: According to scientific studies and opinions of experts (dermatologists, aestheticians), photorejuvenation can offer benefits. The method acts on the deeper tissues of the skin, beyond the outer layer, and has a beneficial effect.

Note:
I am not a healthcare professional. My review is based on personal experience and research. It is advisable not to take my words as facts.