Why do pen caps have holes at the end?
Why do pen/marker/highlighter caps have holes in them?
While there are ball point pens with many different colour inks, why is it only the black, red and blue inks that seem to work well? Why do I have black little lines on finger and toe nails? How can a Sharpie marker cause you ink poisoning? Does the ICAI do slacing of marks? Office Supplies: Why are blackboard erasers colored the way they are? What is this black line on my thumb nail? Can I use any other ink (except blue and black) to highlight points in english in boards? How do I remove permanent marker from rubber? How do you remove permanent marker from walls? Why don't we have elbow caps? How can I remove permanent marker from glass? Why do all golfers wear hats/caps? How can you remove permanent marker from plastic? Why are the alphabet keys on a keyboard jumbled? How are left and right thumbprints related? Does most of the ink contained in pens never get used up? Why do I have a white line across my teeth? Why are bulletproof vests made of ceramic plates? Why is there a color bar on toothpaste? Why do some black people wear silk caps to bed? What's the best way to remove permanent marker from glass? Why does Batman imprint a bat logo on criminals in Batman v Superman? Why are some glass cups frosted? How are dark rings formed around my neck? Why do seals have black teeth? Is there any meaning behind the color codes of toothpaste (green, blue, red and black)? What is the cap? Why not remove nail polish? Why wear chipped? Pens: What makes blue ink better for memorization as opposed to black ink? How do you remove permanent marker from your shoes?