The Correctmarker Refill station ensures that you can reuse the Correctbook marker when it’s empty. One jar of refilling ink can be used 10 to 12 times. One pen can be refilled up to 4 times. Talking about sustainability, right? Plus you don't need to buy a new pen right away when your current one is empty. Correctbook also donates these refill stations in Africa because that is more eco-friendly than replacing empty markers.