RUIKE Knives officially launched three of the M Series knives- the Titanium Series, which has the nicer materials and the lighter weight, recently. Two of the three models in this line, the M108-TZ and M121-TZ, are upgrades to existing designs: the 108 and 121. The third knife, the M875-TZ, appears to be a new design exclusive to the premium line.
See the KnifeNews report in the link below.