is that a vibrating seatpost or something? why the 9v?
There are two different bikes in that composite image, a SRAM equipped Tetra and then a Dragonfly with Calfee's internal (seatpost mounted) Di2 battery.
@gbj_tester started
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There are two different bikes in that composite image, a SRAM equipped Tetra and then a Dragonfly with Calfee's internal (seatpost mounted) Di2 battery.