Pentel e-BALL Ballpoint Ink 0.7mm pen QTY:10xBLACK They’re perfect for everyday writing thanks to the long lasting ink cartridges. The oil based ink is designed to be permanent and durable. You can write for longer without your hand fatiguing thanks to the comfortable rubber grip. These pens are made using 78% recycled materials. Refillable with BKL7 refill