Does the AltMill come with the SuperLongBoard?

The AltMill will come with a specialized variant of the SLB (named the SLB-EXT) which allows for use with a higher 48V power supply and with external driver support. Features that the SLB comes with, such as independent 4th axis control, RS485 protocol, and more, will be shared between the AltMill and LongMill.

The SLB-EXT does not come with integrated drivers, as it is designed to use external drivers integrated with the close-loop steppers directly.

An SLB used on the LongMill is not compatible with the SLB-EXT used on the AltMill. The SLB-EXT used on the AltMill is not compatible with the LongMill without significant added electronics such as drivers.