The World&';s Most Innovative Weight Vest Breathe better when rucking or training - with our innovative Curved Ruck Plates (yes there&';s a big hole in them, yes it works great), you can talk better to the person next to you, or push even harder in your training without suffocating your diaphragm. Combine breathing better with rucksack straps that disperse the weight expertly, and this is a best in class weight vest. We believe that the more comfortable something is, the more you&';ll want to use it. And given all the gains to be had from carrying weight, we hope you use it hard and have fun in the sun doing it. Sizing: L is designed to fit most men. The front and back panels are identical across sizes, the difference is in the shoulder straps and cummerbund. As a result, the S may sit higher on bigger people.