The Yongsheng piston-filled fountain pen with improved versions of some of the best features on piston-filled fountain pens. For instance, the knob for the piston mechanism locks when in the fully retracted position, ensuring that there won’t be any bumped-knob-related accidents. Also, the entire piston assembly is clear, other than the piston itself. Finally, the feed is clear as wel. <br><br> <b> SPECIFICATIONS: </b><br><br> <b> Nib</b> : High quality nylon hair ; <b> Cap</b> : Screw Type<br> <b> Length</b> : 138mm; <b> Diameter </b> ：14mm; <b> Weight</b> : 25g<br><br> <b> Package Include: </b><br><br> 3 x brush pens , <b>Ink not included</b> due to safety reason<br><br> <b> Precision Anti-leaking Rotation Design </b> : operating the piston while ink is in the pen will cause ink to leak out of the pen. You can twist the knob end of the barrel in clockwise to lock it until you hear a "click"