hh3cDot11RRM11acMultiCastVhtMcs 1.3.6.1.4.1.25506.2.75.8.1.1.15

Specify the MCS index for 802.11ac multicast rates. The value 255 indicates that no MCS index is specified. No MCS index is specified for 802.11ac multicast rates by default. Besides, it must be configured together with the node above.