Can I attach a rear rack child seat or trailer with the Blix Ultra?
While you can attach a trailer or child seat on the rear of the Blix Ultra, the Ultra Rear Rack (150lb limit) will need to be purchased in order to use a rear rack child seat.
This bike does not have any special accommodation for trailers (unlike the Packa Genie), but any trailer compatible with e-bike rear axles should work. A good example would be the Burley Bee kid trailer which has a 12mm hole on the axle hitch to accommodate an e-bike axle.