This listing is for someone who wants to go teal... for a very long time. This dye is a demi dye. We have had customers go over 6 months without needing to re-dye...less fuss for people who like teal and want to stay teal. Each sale here gives you two units...so the price is for two units which will carry you over a year. How long it lasts really depends on individual factors: application (did you follow directions), was your hair cleaned of all residue, etc. is your hair healthy, etc. But overall, a demi dye will last months...it is the rule, not the exception. If you need a bleach kit or other tools, message us and we can provide them. Thank you.