It says:

"The current eCrate kit requires a GM 4-speed automatic transmission with an external mode switch (e.g., 4L60, 4L65, 4L70, 4L75 Transmissions). This helps to make the eCrate conversion easier for vehicles that already have a conventional driveline, plus it provides extra torque in lower gears and extra speed with overdrive. We are working on bringing a direct drive variant option to our eCrate portfolio."