The Quick2Wire I2C analog extyender board has four 8-bit analog inputs and one 8-bit analog output.
You can additional information on the Quick2Wire website
28-17734 - Raspberry Pi Interface Board
The Quick2Wire Interface Board gives you easy access to all the features on your Raspberry Pi’s expansion header with added protection of not creating a dead Pi
28-17735 - I2C MCP23017 Raspberry Pi Port Expander Kit
The port extender board gives you an additional 16 GPIO pins to use on your Raspberry Pi, which can be used as digital input or output.
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