When gray hairs start appearing, you may decide to turn to hair color products to cover them up. However, your usual dyes might not do the trick. Joico Vero K-Pak Color Age Defy in 5MB+ Medium Mocha Brown uses a more concentrated formula to deeply penetrate stubborn gray locks. It softens hair and gives it a more youthful appearance. It is great for those with more than 50 percent gray hair.