Hach BioTector B3500dw User Manual page 40

Table 3 BioTector motherboard components
1 Motherboard
2 Battery (Varta, CR2430, Lithium, 3V, 285mAh)
Hazardous area analyzers may have a special battery. Contact manufacturer for details.
3 Processor Board
4 MMC/SD Flash Memory Card Slot and Memory Card
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