Do you know how to determine if a mirror is 2-way or not? A policewoman who travels all over the U.S. giving seminars and techniques for businesswomen passed this on. There have been cases of people installing 2-way mirrors in female changing rooms. It is very difficult to positively identify the surface by looking at it. So, how do we determine with any amount of certainty what type of mirror we are looking at? Just conduct this simple test: Place the tip of your fingernail against the reflective surface and if there is a GAP between your fingernail and the image of the nail, then it is a GENUINE mirror. However, if your fingernail DIRECTLY TOUCHES the image of your nail, then BEWARE! IT IS A 2-WAY MIRROR! So remember, every time you see a mirror, do the "fingernail test." It doesn't cost you anything. REMEMBER. No space, leave the place. Ladies: Share this with your girlfriends, sisters, daughters, etc. Men: Share this with your wives, daughters, daughters-in-law, mothers, girlfriends and/or friends.