Our vest sizes are based on the waist measurements at the belly button, not lower. Please do not use jeans or loose jackets as your size reference. Your vest will not fit correctly if you do.
Chest width is proportional to the waist, so if your waist fits, then your chest will be ok too.
If you have a bodybuilder like upper body with a wide thick chest and slim waist or vice versa with a big belly but slim chest, most likely none of our vests will fit you properly, you will need a custom fit made-to-measure vest.
We recommend having at least 1" gap on both sides when wearing the vest for comfort, concealability, breathability, and mobility.