Schwarzkopf Igora Royal Oil Developer 1L/33.81oz (9% / 30 Vol) 30 Volume-30 Volume This developer should be used with all Schwarzkopf IGORA ROYAL colors. The new high-definition technology with oil content in the developer ensures an extra care and long-lasting results. 3%/10 Vol – 1-2 Levels of lift; 6%/20 Vol – 2-3 Levels of lift/Gray coverage; 9%/30 Vol – 3-4 Levels of lift; 12%/40 Vol. 4-5 Levels of lift. When purchasing this product buyer agrees, that they are aware of consequences from its use, and will not hold the seller responsible for unwanted results or damage to hair, skin, nails, or health. Seller does not manufacture any goods it sells and therefore cannot be held responsible for the outcome from the use of any sold products.