The middle rod is approximately 2.09inch/5.3cm long and 0.08inch/0.2cm in diameter, sized to fit the hole diameter of most beads. Material: The main body of the loose ball pen is made of reliable plastic, which is sturdy and not easy to break, deform or fade. Dry ink flows at an even speed, providing smooth writing with daily wear and tear, suitable for signing, note-taking, writing and more. Unlike the ballpoint pens that are pressed, this ballpoint pen opens in bulk by rotating the pen body. When you run out of ink, just take out the refill from the bottom and rotate to replace it, easy to use. Perfect combination with chunky bubblegum beads, rhinestone beads, cute metal beads, large hole euro beads, glass bead pendants, tassels and more. Beaded pens bring endless creativity. Colour:Blue Material:Plastic Size:14cm Package Contents: 20 * pen Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.