Going to be stamping A LOT? This listing is for black refill ink for my Brother brand self inking (pre-inked) stamps. After approximately 2,000 impressions, your stamp will need re-inking. With proper re-inking your stamp can last up to 50,000 impressions! This is a 0.67 oz bottle of refill ink, only 10 drops are needed for re-inking so it will last you a very long time.