PR-650 SpectraScan has been the most widely used spectroradiometer in the world - the workhorse of the industry. The new PR-655 replaces the world renowned PR-650 with a plethora of enhancements. This unique, portable battery powered instrument utilizes a fast-scanning 128 detector element spectrometer with a spectral resolution of 3.12 nm per pixel and is supplied with an automated measure shutter. A 1° aperture is standard equipment with the PR-655 - an optional ½° aperture can be ordered. Other hardware features include AutoSync® for automatically synchronizing to the source refresh rate insuring the utmost accuracy, an optional External Trigger port allowing remote measurement activation from either a push button or peripheral device, a Secure Digital (SD) port for measurement storage, and a long lasting rechargeable Lithium-Ion (Li-Ion) battery.