This is the banner image at the top of your listing, so it carries a lot of weight for first impressions.

Your business name appears in white text over the cover image.  It is recommended that you use a dark background / image so there is enough contrast for it to be read. 

Cover images resize automatically for mobile and desktop, which means the very top and bottom of your image can get cropped depending on the screen. Keep your key visual details centred rather than near the edges.