Vortex binoculars for car glove boxes or slightly larger jacket / coat pockets.

No more than a 10x magnification, as the smaller binoculars tend to be around the same size if they are 6.5x, 8x or 10x magnification.

The next number, 28mm or 32mm is the fat end of the binocular with the slight downside that as the fat end grows, so does the size and weight of the binocular. The smallest are 8x26 or 8x28 that are between 360 and 390 grams, which is the same weight as 10x26 and 10x28.

6.5x32, 8x32 and 10x32 tend to be a little bigger and are heavier from 410 to around 440 grams, but with the "fatter" end they do suck in a bit of extra light. Often considered a second-pair rather than the prime binoculars being used, they still maintain all the features of their bigger brothers and sisters so while small, they still perform.