never used. Biochrom WPA Colourwave CO7500 colorimeter, a device designed for educational and laboratory use. It features an 8-wavelength filter wheel covering a range from 440 to 680 nm. The instrument is compact and lightweight, designed for durability in teaching laboratories. It operates with a simple three-button interface for Reference (R), Test (T), and On/Off functions. The colorimeter can be powered by mains electricity or an internal rechargeable NiMH battery.
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