The Subpage Fullwidth supports header images. The header image will have a center focus throughout each device that it is viewed on. It has a set height of 300 pixels.

Recommended Subpage Header Image: 1100 x 300 pixels (note: you can increase the image width for larger screen sizes, but the visible image height will remain at 300px)

To edit the Subpapge Header Image, navigate to Content > Pages > click to edit your page > 'Header Image'