20-pack black angle beveled washers with 5/16" ID, designed for cable railing stair ends and sloped deck installations. Made from marine-grade T316 stainless steel with a durable black finish, these 30-degree beveled washers offer excellent rust and corrosion resistance for indoor, outdoor, coastal and extreme weather use. The precision beveled edge creates a flat, stable surface for cable terminals on stair railings angled 25 to 40 degrees. It eliminates wire rope deflection, reduces tensioner wear, and ensures clean, professional alignment. Each washer has a 5/16" inner diameter and 5/8" outer diameter, providing a secure fit for standard 5/16" threaded studs. It is fully compatible with 1/8" and 3/16" cable railing hardware and stainless steel wire rope systems. Smooth, burr-free edges mount flush on wood, metal or aluminum posts and resist deformation during installation, making the process fast and easy for both DIY users and contractors. This 20-piece value pack provides enough hardware for a full staircase run. It delivers long-lasting durability and a modern, clean appearance for any sloped cable railing system.