[darkpuma]

I think the case he's talking about adds about 150g or so. If you're an ultralight hiker who's counting the grams, there are probably better options on the market. Otherwise I don't think many would notice during their daily routines.

[js2]

Something like this right?

https://www.amazon.com/gp/product/B01N1M1WRU/

That's what's on the 11" MBAs my kids have. It's 8.3 ounces (235 grams) and quite noticeable. I guess you could use just the top shell.

[rangibaby]

I used one years ago (2011 MBP 13), it made the top case top heavy for the screen hinge to support which made the screen a bit floppy.