This article describes the optimal USB-C cable length for Elo products

USB Type-C specification recommends a maximum cable length of 4 meters (approx 13 feet) for passive cables. This information is from the official USB Type-C Specification, section 3.1.3 Compliant USB Type-C to Legacy Cable Assemblies

Generally speaking, the shorter the cable, the better transmission rate when it comes to USB-C.
Elo's recommendation is to never exceed 6-feet on USB-C connections. Longer cable lengths may not allow the transfer of video, data, and audio. Elo P/N: E710364 is recommended for use on all Elo products.