For runners looking for a little self-sufficiency without weighing down their stride, the Duro LT is a great option. With pocket space for flasks, nutrition and gear to boot, it'll take you from training to lightweight trail days in record time. Plus, the Duro/Dyna family is sustainably designed with 100% recycled materials. VESTPACK SIZING The Duro/Dyna 6, 1.5 and LT come in six sizes: men s S, M, L and women s S, M, L; the Duro/Dyna 15 comes in four sizes: men s S/M and M/L and women s S/M and M/L. Based on torso length and chest circumference, these packs are sized like apparel. The surface area of the harness evenly distributes the weight of the pack on both the smaller and larger volumes. Measurements should be taken at widest part of chest slightly below armpits. MEN'S DURO 6 | 1.5 | LT INCHES S: 29.5 - 35 in M: 35 - 41 in L: 41 - 47 in CENTIMETRES S: 75 - 90 cm M: 90 - 105 cm L: 105 - 120 cm MEN'S DURO 15 INCHES S/M: 29.5 - 41 in M/L: 41 - 47 in CENTIMETRES S/M: 75 - 105 cm M/L: 105 - 120 cm. Reliable performance High-quality construction Long-lasting durability Durable construction Wide range of features Ergonomic design.