0.7 mm. New! Water resistant. Fade resistant. Fraud resistant. Smoothness. Retractable gel pen. Water, fade and fraud resistant ink. Fast-drying. and smooth writing. Premium design with a comfortable grip. BIC Performance Policy (US and Canada): If you are not satisfied with the performance of this product, please return it to BIC and we will gladly replace it at no cost to you. www.bic.com.