As a teacher, and because of the endless paper handling, it is so hard for me to maintain a decent manicure . Beause of this, and the dry weather her in Las Vegas, I tend to have rough fingernails that could potentially snag my yarn (and have on several occasions). SOO…I carry a nail file in my tool kit to use when I notice that my nails are attracting a lot of unwanted yarn fiber attention. Also a great way to keep those bamboo needle points sharp and ready! Happy knitting!!