Humminbird SD/MMC Card Reader

Features: Plugs into a USB port on a computer and allows your computer to read SD and MMC cards. This will allow you to update the software on your unit. This accessory also includes a 16MB MMC card. For use with: 931C, 937C, 947C 3D, 981C SI, 987C SI, Matrix 47 3D, 727, 737, 767, 777c2, 787c2, Matrix 12, Matrix 27, Matrix 37, Matrix 67, Matrix 77, Matrix 87.