the Laxa Fly Vest is made of a solid and fast drying 320 denier nylon fabric, the inside features a mesh for good breathability. The shoulders and neck have a padded cushion for comfort and even distribution of weight when heavily loaded up. All zippers are top quality from YKK and the vest has an elastic adjustment in the hem for a snug fit. The two vertical pockets on the chest are suitable for boxes like our slim and small ultra light. The large waist pockets can take the largest Dewitt 18 room boxes and Large C&F.