There seems to be a trend to make ball point refills feel smoother as one writes--witness the Uniball pens, for example.Monteverde has seized upon this and has come out with their own version of these "super-smooth" ball pen writing refills.They are inexpensive and well-worth the money.I recommend them, especially for the times you are trying to find a refill that is for a capless rollerball, and they are not to be had! this comes in a worthy second, but probably is more reliable,and will last longer.