KOOTIPS Mini Solid Brass EDC Pocket Pen, Portable Delicate Signature Pen, Utility Key Ring Pen EDC Writing Tool - Keyring attached, idea for note-taking, signature, and etc Bolt-action mechanism - Easy and quick to expose and retracte the nib Easy Refills Accessibility - Compatible with Parker style series ballpoint cartridges Hefty Pen - Makes it a smooth writing instrument. Size: 9cm/3.6inch Comfort Grip Design - Better holding feeling in hand Hefty Pen - Makes it a smooth writing instrument