Hello, I have attached links below to the specifications of each mount.
https://www.samsung.com/us/televisions-home-theater/television-home-theater-accessories/televisions/no-gap-wall-mount-for-65----55--q-series-tvs-wmn-m11eb-za/?redir=WMN-M11EB/ZA#specs
https://www.samsung.com/us/televisions-home-theater/television-home-theater-accessories/televisions/no-gap-wall-mount-for-65----55--q-series-tvs--2018--wmn-m12eb-za/?redir=WMN-M12EB/ZA#specs
^Britt