For some reason, I thought the yellow holstered 70 series pre-dated the 80, but I think I was wrong about that.
The 70 series used the more squared-off, green holsters until the 80 series came out, then they switched to the yellow or grey holster with the matching rounded theme of the new 80 series.
The difference in the LCD surround of the 70 series is the key - if it's grey, it's the newer yellow or grey holster. If it's green (well, greenish gray, like the older cases) it had the older holster.
I can't keep this stuff straight - too many details for my mind to keep up with.
I like the yellow meters in grey holsters.