These Studymate Retractable Ballpoint Pens contain an oil-based ink which flows smoothly for an easy and comfortable writing experience. They're retractable so you can keep the nib protected when you're not writing. Features: Each pen has a 1 mm nib to produce a medium line. You can use them for everyday writing on a variety of paper types. The ink is oil-based to flow smoothly while you write. There's a pocket clip built-in so you can carry your pen with ease. The barrel colours match the ink colours so you'll be able to easily find the right pen. There are an assortment of blue, black and red pens in this pack. This pack contains 12 pens. Studymate products are built with contemporary design, everyday durability and reasonable prices in mind, making them popular among parents and students alike when shopping for school essentials.