This object selects the frame CoS policy for the dynamic encap tunnel -- explicitly fixed or rcos-mapped in this object's own syntax, unlike the static tunnel's version which references a shared textual-convention type -- as the description states. The choice works the same way as on static tunnels, determining whether traffic keeps distinct QoS treatment via a mapping table or gets collapsed to one fixed marking, but here it's configurable per individually signaled LSP instance. For example, choosing rcos-mapped(2) lets several customer priority classes carried over this dynamic tunnel retain distinct treatment through the referenced CoS map rather than all frames being flattened to one class.