This product is a permanent hair colour, and the manufacturer states that it helps to blend or cover grey hair. That means it can be used to refresh your natural colour or to cover regrowth, but the level of coverage depends on several factors.
If you have a low percentage of grey (say, less than 30%), a single application usually gives good coverage. If you have more grey or very resistant grey hairs, you may need to leave the colour on for the maximum time stated in the instructions, or you might need a slightly higher-volume developer – but always follow the instructions that come with the product. The metallic tone itself does not change the coverage mechanism; it still works like a standard permanent dye.
To know exactly how well it covers your grey, do a strand test on a small, hidden section of hair. Apply the colour as you would normally, wait the recommended time, and rinse. This will show you both the colour result and the grey coverage. If you have very stubborn grey, you may need to repeat the process or consider a dedicated grey-coverage product, but this shade is designed to help.