The DR1900 is perfect for use in the field because it is the lightest and most compact portable spectrophotometer. It also can perform that largest number of tests of any portable instrument. Underneath the rugged exterior, the DR1900 has the largest number--over 220--of the most commonly tested preprogrammed methods already built in. You can also use the easy-to-use interface to create your own methods. Also, it is flexible because you can use the widest range of vial sizes of any other spectrophotometer.