Vitamin C serum for sensitive skin in a 60 ml size typically refers to specialized formulations designed to brighten skin and reduce dark spots without causing the irritation common with high-strength pure ascorbic acid. These serums often use stabilised derivatives like Ethyl Ascorbic Acid or lower concentrations (around 5–10%) to ensure they are gentle enough for easily irritated skin. 
While many standard serums come in 30 ml bottles, the 60 ml size is common for specific brands or value “duo” packs. Below are prominent options matching this specific criteria: 
Key Benefits for Sensitive Skin
Gentle Brightening: Uses stable forms of Vitamin C (like 3-O-Ethyl Ascorbic Acid) that are less acidic and less likely to cause redness.
Hydration Boost: Frequently paired with Hyaluronic Acid or Panthenol to soothe the skin barrier during treatment.
Antioxidant Protection: Shields the skin from environmental stressors and UV damage, which can otherwise trigger sensitivity.
Reduced Irritation: Typically free from synthetic fragrances, essential oils, and harsh parabens that often bother sensitive types.
Usage Tips for Sensitive Types
Patch Test: Always apply a small amount behind the ear or on the inner arm for 24 hours before full facial application.
Start Slow: Use a smaller amount first and adjust frequency gradually, potentially starting with alternate days.
Moisturize: For very sensitive skin, apply a toner and moisturizer immediately after the serum to lock in hydration and buffer the active.
Sun Protection: Always follow up with a broad-spectrum sunscreen in the morning, as Vitamin C can increase sun sensitivity.