This article provides more information on the type of HDMI cables Elo recommends

Elo recommends HDMI cables rated 2.0 or higher with a maximum length of 25 feet.

HDMI cables are available in a variety of standards. Using HDMI cables rated 2.0, also known as Premium High Speed HDMI, or higher will ensure compatibility with all current Elo hardware. At lengths greater than 25 feet attenuation of the signal is likely to cause issues. If a longer length is needed options include HDMI extenders over category cable, fiber optic HDMI cables, or active HDMI cables. Elo does not test solutions for longer HDMI cables, and is unable to provide support relating to their use or functionality.