This is a great question I will be happy to answer for you today. Hair Color starts with the level of hair. This is the number you see which is 5. 5 is going to be middle of the road Brunette. 1 is black and 10 is platinum everything else falls in between these levels. The W is going to stand for Warm which is a tone. Warm will have reds and coppers as the base in the color. The V will stand for Violet. The W is in the first spot so that is going be the primary color/tone and will equal 2 parts. The V is in the second spot which is the secondary color/tone and will equal 1 part and be more of the undertone of the hair. I hope this answered your question today. Have a Beautiful Hair Day!

COLORCHARM Permanent Gel| Hair Color for Gray Coverage| 6R Red Terra Cotta| 2 Fl Oz

COLORCHARM Permanent Gel| Hair Color for Gray Coverage| 6R Red Terra Cotta| 2 Fl Oz

Q: What if you dont use the color developer?

I have never tried using hair color without a developer. Developer opens the hair folicle to allow the color pigments into the hair fiber, resulting in lasting color.

Q: Where are the color choices

No idea. These are professionals colors. You could google it and see what colors, color charm carries then see if amazon carries it

Q: Does 7N + 1oz 7NG results in the model’s hair color?

Thank you for contacting Wella! We appreciate your interest in our products! If you are referring to the model on the Amazon selling page in the video for Wella Color Charm Hair Color, she has a warm brown shade in the Color Charm Permanent Hair Color applied to her hair. To replicate her shade, you can try shade 5NW Light Natural Warm Brown mixed with a very small amount of shade 5WR Allspice. When using our hair color, and especially when mixing shades, we advise to perform the strand test in addition to the allergy test to preview the color results before coloring over the rest of your hair. Make sure to use the 1:2 mixing ratio with our Wella Color Charm 20 Volume developer. You can reuse any unmixed hair color in the rest of the bottle or tube within 6 weeks after opening so long as it is sealed and stored in a cool, dry place. For more information, please contact Wella at 1-866-722-4146.