Extend the life of your pen with Montblanc pen refills. This refill helps to ensure that you will have plenty of ink, so you can keep using your favorite writing tool. Keep the refills nearby and never worry about low ink again. Keep refills handy so you never run out of ink. For Giant Ball pens. Refill - designed for use with a specific refillable, helping you save resources and money by extending the life of your product.