The laser unit adds a much requested red sighting laser and an expanded temperature range to 662F (or 350C).  This unit has an adjustable emissivity setting for precise calibration and perhaps best of all a tight infrared "cone" distance to spot ratio (D:S) of 6:1.  That means at a distance of 6 inches you are reading an area just 1 inch in diameter.  At a distance of 2 feet an area of just 4 inches as compared to our wider D:S ratio of 1:1 on the basic unit.Includes a wrist strap and two batteries.