When it works it's great, but it doesn't always work. This is my 3rd and it stopped working so I figured I would check the battery. THAT IS IF I COULD OPEN IT. This is the second one that I couldn't even get the battery compartment open without mashing it. The teflon o-ring is too dam tight The dam thing wouldn't work but after I beat the battery compartment open it started to work. I can no longer give these pens Kudos. Time to move on.