It's supposed to be a more durable meter than the 121gw.
Actually that's an interesting point.
Certainly more rugged from an electrical point of view, but from a mechanical point of view, I don't know. The 121GW is a full holster based meter, this one is an overmoulded split case design. Similar to say a Fluke 77 IV
Of course the 77 IV is stupidly rugged, so it's not a matter of just having lack of a thick holster. It
feels pretty rugged.
Now that I think about it, yeah, it's kind a competitor to the Fluke 77 IV in terms of look'n'feel of the overmoulded case, no fuse access via battery compartment, but with extra stuff like EF testing, 60,000 count, proper low current support, way better specs etc. i.e. a proper "electronics" version of a Fluke 77 IV.