1. ISO rating.  When you are looking at laser distance meters an ISO rating is a world wide rating system for water and dust protection.

  2. Certificate of Accuracy - Look for a Certificate of Accuracy with the actual measurements of your laser distance meter on a calibrated range.

  3. No moving parts.  If you hear click-click-click when you hit the button on a laser distance meter, you are using older tech that is based on the same principle as the mechanical shutter on a camera.

  4. An automatic or intelligent end piece.  Many common measurements like measuring a door or window rough opening, or across foundation forms to check square are diagonal measurements that require your laser distance meter to measure into a corner.  The solution is a flip-out extension that is thin to fit all the way into the corner.

  5. Configurable "beep" - It sounds like a no brainer, but having a sound that tells you a measurement has been successfully taken is a key.