Can anyone tell me about the hair grading system?

I have never heard of a universal grading system for hair quality. Generally there are specified standards however its still a VERY buyer beware market because anyone can claim they sell hair and it is Remy or top grade or whatever else they want to say about it. That’s advertising. The same thing happens with cosmetics. With hair it’s even more difficult because some people simply LOVE hair that I think is crap and vice versa. Not to mention that almost all of us have different hair issues and textures that we are trying to match as closely as we can. So hair that works for me, may not work as well for you etc...I think a lot of it is based on your needs and what you want from extension hair. Some of us require longevity and others like to swap their hair out weekly so affordability is more important to them than top of the line quality. Its all about meeting your needs.

I have heard of a hair grading system that uses letters to denote the qualities, such as 'A' hair is better than 'B' hair, and so on.