Keratin Treatment is the popular one in the UK, because it takes away frizz and eases their natural hair and gives back shine etc. With the original Brazilian solution that I don't think is available in this country because of its strength. Brazilian is used to more so straighten out the hair almost like a relaxer but not a relaxer. NanoKeratin & 72 Hair are the ones I have used and don't do anything other than make the clients hair silkier, softer less frizz for around 2-3 months using the home care they provide. Sulphate free etc.