The 587c HD DI units were a Black Friday unit as were a few other DI models. Seems that they were quite popular and are still available at some retailers. I do not know if they will be added to the regular line-up for next year or not. If they are they will get added to the Humminbird web site. These should have the same sonar specs as the other DI units: 788ci HD DI, 597c HD DI, 581i DI, 570 DI, 385ci DI and 345c DI.