The Fleck3B is the latest in a series of nodes developed by CSIRO.  Its main features are:

• Size 50×60mm, mass 28g
• Power supply 3.4-8V
• Inbuilt solar charging circuit for NiMH batteries
• Monitoring of battery voltage, solar voltage, and charging current
• Atmega 1281 processor with 8kbyte RAM and 128byte program flash
• Real-time clock chip that can interrupt the CPU allowing very deep sleep modes
• nRF905 radio, 40 channels at 915MHz, radio range of 1000m
• 1Mbyte flash memory onboard
• Expansion bus connector for Fleck daughter boards
• Screw terminals for convenient connection of analog and digital sensors