Note, ironic that a Doctor gave that to you, since the only advice I have to give is NEVER EVER lend a pen light to a doctor. I was in the ER one night with a "Client" when a doctor walked up to me and asked if he could borrow a small flashlight. I handed him my pen light. He briefly shined it on his palm and said, "Yup, you could see a cervix with that," and turned around and pulled the curtain shut. A few minutes later he walks out and tries to hand it back to me saying, "Thanks." It took me MANY santitary wipes before I was willing to put that back in my pocket.