nm/ 532nm 2-color Red / Green Beam Gypsophila Pattern Adjustable Focus Laser Pointer with Holder<br>Functions<br>1. Teacher / lecturer - For classroom teaching、 it is like a pointer infinite、 at any corner of the classroom you can easily refer to the planning board and be absolutely an assistant for teachers<br>2. Business person / Conference Speaker - Product demonstrations and meetings explained、 let your speech become capability and with customers be more relaxed and natural<br>3. Museum / Exhibition / tour guide - When you are in the face of tentacle difficult and do not know what the objectives of the beam、 it can help you indicate target easily and accurately<br>4. Field travelers / explorers - For outdoor adventure、 indicating distant targets and a distress signal issued. It is the preferred equipment to Make your trip more interesting for outdoor activities.<br>5. Astronomy enthusiasts - For astronomy star、 purple laser emitted beam is a very beautiful purple line. Be Well suited for observing the night sky and can accurately indicate the position of the stars<br>6. Mining field / construction workers - For remote accurate indication / measure buildings. Avoid approaching the danger zone. Allow you command spot outside thousand meters like your sight<br><br>Install battery<br>1. Unscrew the cover of the laser pointer. <br>2. Take out the battery and be ready to put it in<br>3. Place one 18650 or 16340 battery cathod