Earlier this month, Microsoft launched its new devices Surface Book and Surface Pro 4.  Pre-order of the device had already been started and it will be start shipping today.
Now Microsoft has released a new firmware updates for both devices and it can be downloaded from Windows Update or Microsoft Download Center.
Description:
Cumulative and current firmware and drivers for the Surface Book & Surface Pro 4. This firmware and driver package contains drivers for all of the components in the Surface Book & Surface Pro 4, as well as updates to the system firmware that have been released via Windows Update. These drivers and firmware are compatible with Windows 10, including Enterprise versions. The driver MSI and ZIP files include all of the drivers and firmware needed to deploy custom images of Windows on your Surface devices. For convenience, the Ethernet dongle drivers are included as separate packages, but are also included in the ZIP and MSI. Additionally, the WinTab driver is provided for those professionals needing WinTab compatibility with certain Surface Pen enabled applications.
Download Firmware update for Surface Book
Download Firmware update for Surface Pro 4