This read-create object sets the class-of-service value, 0-7, for this IP Management Tunnel, which per the description also becomes the 802.1p priority bits for VLAN-based tunnels, on both VLANs if S-TAG is enabled. Admins tune this so management traffic gets appropriate queuing priority as it traverses switches that respect 802.1p markings. For example, to ensure management traffic isn't starved during congestion, an admin would set this CoS value high so it's prioritized in the p-bits of the tunnel's VLAN tag(s).