SITKA GRINDER HOODY. The Grinder Hoody was born to pull double-duty for waterfowl season. Worn between a next-to-skin layer and a shell for core insulation or as a breathable outer layer. The Grinder has become the go-to high-performance intermediate layer for duck guides and is an integral piece in a waterfowlers system. GORE OPTIFADE CONCEALMENT. GORE OPTIFADE Concealment Waterfowl Marsh is designed for layout and blind hunting in the marsh, standing crops, and cut stubble fields. GORE OPTIFADE Concealment Waterfowl Timber is optimized for engagement distances of 10 to 40 yards in the darker environments of flooded timber. WHY WE MADE THIS. Waterfowl season is a grind and hunters have been looking for a durable lighter-weight insulation piece to get them through the season. They needed a jacket that could pull double duty: from dynamic workloads of getting to the field and setting up decoys to transitioning to insulation for periods of static activity in the blind.