This object sets the beginning of the label range reserved for manually-assigned static MPLS tunnels, as the description states, with the constraint that it must never overlap the separately configured dynamic label range. Because changing it requires a device reboot to take effect, this isn't something an admin adjusts casually -- shrinking or moving this boundary reshapes how much of the MPLS label space is set aside for static LSPs versus what's left available for RSVP-TE-signaled dynamic tunnels, and doing so needs a planned maintenance window. For example, setting this to 100 instead of the minimum allowed value of 16 deliberately narrows the low end of the static pool, freeing more of the low-numbered label space for other uses.