Black Diamond Project Twill Long Sleeve Shirt - Men's Creek Blue/Charcoal Large. Featuring a certified organic cotton twill this long sleeve shirt has two chest pockets with button closures and reinforced elbows for added durability. Designed for year-round use the Project Twill is a workhorse button down built for the climbing life and everything in between. Specifications for Black Diamond Project Twill Long Sleeve Shirt - Men's: Manufacturer: Black Diamond Age Group: Adults Gender: Male Features of Black Diamond Project Twill Shirt - Men's Reinforced elbow patches Two chest pockets with buttons Reinforced elbow patches Package Contents: Black Diamond Project Twill Shirt - Men's Black Diamond AP7530919660LRG1: Project Twill Long Sleeve Shirt - Men's Creek Blue/Charcoal Large