Description ***Sitka&';s Standard Fit is designed to accommodate layering for added versatility across early-to-late season conditions.*** The Sitka Ambient 100 Shirt Jacket brings the adaptable warmth of the Ambient collection into a versatile everyday layer for changing conditions. Its 100-gram PrimaLoftA(R) Evolve insulation provides breathable warmth during active use, while durable stretch nylon resists snags and pilling. A DWR finish helps shed light precipitation, and snap-front styling with zippered hand and chest pockets adds practical comfort for daily wear or time in the field. Specs Insulation 100 grams PrimaLoft Evolve Material Nylon stretch fabric with DWR finish Manufacturer Warranty Warrantied against manufacturer defects Sizing Size Chest Sleeve Medium 39" - 41" 34" Large 42" - 45" 35" Large Tall 42" - 45" 37" X-Large 46" - 49" 36" X-Large Tall 46" - 49" 38" XX-Large 50" - 53" 37" XXX-Large 54" - 57" 38" How to Measure: Chest Measure around the fullest part of your chest, keeping the tape under your arms and across your shoulder blades. Sleeve Bend your elbow and place your hand on your hip. Measure from the center back of your neck, across your shoulder, down your arm, over the elbow, and to the wrist bone.