Filson Field Jac Shirt Washed Oatmeal

The Filson Field Jac Shirt in Washed Oatmeal is a versatile overshirt built for transitional conditions and everyday layering. Based on Filson’s original Jac-Shirt, a long-standing staple since the 1970s, this version is designed as a practical extra layer for cool days in the field, while remaining clean enough for daily wear off-trail.

Its construction is defined by a strong 9.5-oz. 100% cotton fabric. Filson specifies that this piece is made with the fabric type used for vintage military fatigues, giving it a workwear-oriented character without overcomplicating the design. The midweight cotton uses a reverse-sateen weave, smooth on the inside for easier layering over a T-shirt or lightweight knit. That detail makes it particularly useful as a grab-and-go outer layer when temperatures shift through the day.

The garment-washed finish softens the overall hand and gives the shirt a more broken-in feel from first wear. In practice, that means less stiffness than a rigid overshirt, while still retaining the structure expected from a substantial cotton layer. The result sits comfortably between a shirt and a lightweight jacket, offering enough substance for cooler mornings, spring evenings, and mild autumn use.

Function is kept straightforward. A button-front closure and spread collar maintain a clean silhouette, while button-adjustable cuffs allow minor fit adjustment depending on layering or preference. Two button-flap chest pockets provide accessible storage and reinforce the military-inspired field aesthetic. The straight hem is intended for untucked wear, which suits the overshirt format and gives it a more relaxed, practical profile.

This is a piece that works well as a light outer layer over a base layer, or worn under a heavier jacket when more insulation is needed. The balance of sturdy cotton fabric, simple storage, and easy layering makes it a reliable option for mixed urban and outdoor use.

• Features
• Strong 9.5-oz. 100% cotton construction
• Made with the fabric type used for vintage military fatigues
• Reverse-sateen weave, smooth on the inside for easier layering
• Garment-washed for a softer, broken-in feel
• Button-front closure
• Spread collar
• Button-adjustable cuffs
• Button-flap chest pockets
• Straight hem for untucked wear
• Specs
• Color, Washed Oatmeal
• Material, 100% cotton
• Fabric weight, 9.5 oz.
• Manufacturing, Imported
• SKU, F1420277936-1
• Care, machine wash cold separately, tumble dry low heat, do not bleach, warm iron if needed