Maybe I'm misunderstanding, but ...
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True - all new unit models have CHIRP (which can be shut off and use fixed frequency) ...
But there is still 2d/GPS units without imaging ...
HELIX 10 CHIRP GPS G3N (and larger) does indeed come with SD card slots ...
https://humminbird.johnsonoutdoors.c...737.1568173842
(HELIX 9 CHIRP GPS G3N (and smaller) is micro SD card slots) ...
https://humminbird.johnsonoutdoors.c...737.1568173842
Feature icons under each product listing on the HB website indicates SD card size ...
(One should not trust dealer feature listings) ...
Rickie