"Hair board" recommended this amazing tinted glaze to me when I inquired about any cool or neutral dark brown options ( I would say this is neutral-natural in undertone). I found it on Amazon for roughly $16-18 dollars, which, for just over 10 fl. oz. on my shoulder-length hair, works out to under $2 an application.Basically, you slap on some gloves, apply it to damp & freshly shampooed hair, put Saran Wrap on your head (if you are fancy like me), and wait 15-20 minutes while warming up your noggin with a hair dryer before rinsing. My hair is slightly wavy, fine-textured and there's...a lot of it (although I wouldn't say I have the thickest hair in the world or some nonsense).I don't think it does anything special to my hair quality-wise, but it does add extra shine and deepens my level 6/7 (light-medium brown) hair a shade or two (depending how long it's processed). My BF didn't know what I had done but kept saying I looked pretty the first time I used it (so, on my hair color at least, I would call it very natural). It fades out completely after about a month in my experience.It's a liquid-gel consistency and a little bit runny...I would suggest getting a hair color applicator bottle and brush if you don't already have them, applying a barrier jelly beforehand (I like using antibiotic cream) and to be ready to wipe down any surrounding skin with an old rag after application (just like with semiand permanent dyes).