Material: The Screws are made of SAE 316 Marine Grade Stainless Steel. The preferred steel for use in marine environments because of its greater resistance to corrosion. The Snaps are made of brass and nickel-plated for added durability, rust and oxidation resistance. Multiple Applications: These Heavy Duty Canvas Button Snaps are widely used for boat covers, canvas, Lawn furniture, pool covers, tarpaulins, tents, awnings, sailcloth, clothing, leather and many more applications. The perfect fit for both the indoor or outdoor use. Set Contains: 25x Stainless Steel Screw 10mm / 0.39inch - 25x Stainless Steel Screw 15mm / 0.59 inch - 25x Steel and Brass Cap 15mm / 0.59 inch - 25x Stainless Steel Cap 15mm / 0.59 inch - 50x Stainless Steel Socket 10mm / 0.39 inch - 2 Piece Punching Tool Set Feature: Included 1 Studs. These Stainless Steel Studs are available for clamping onto screw or canvas studs for mounting on hard surfaces in harsh conditions. The snaps with heavy-duty grade construction assures a super firm grip that will remain secure through years or even during the harshest weather conditions. The Complete Set comes in a Sturdy Plastic Transparent storage box that keeps all your important parts well organized and in one place with out losing them.