Most micro sized FPV cameras come with an adapter so that you can fit your 19mm wide micro cam into a 28mm wide frame mount. Sometimes they don't. Or sometimes, it did come with an adapter, but... you lost it. Well, here you go.
Sure, you could just rig something up or 3d print your own, but "ain't nobody got time for that!" Grab one of these molded plastic micro camera adapter for your Remix V2 or other full size camera mount.