the StarLock to Universal blade adapter. : r/Tools
Oscillating Multi Tools Shank Adapter For All Kinds Of Multimaster Power Tools Starlock Oscillating Saw Blades Adapter - Power Tool Accessories - AliExpress
Multitool Adapter™ - Perfect fit for Makita™ - Oslo Tool Company Int.
Starlock Multitool Adapter™ (Screw-System) - Oslo Tool Company Int.