DIMENSIONAL SPECIFICATIONS: Thread Size: #4; Head Dia: 0.21"; Screw Length: 1/4 inch (measured from the flat underside of the head to the sharp tip of the threads). Please verify your required hole depth using this method before ordering to ensure proper fit PREMIUM 304 STAINLESS STEEL & BLACK E-COAT: Manufactured to strict ISO 7049 standard specifications. Forged from solid 304 (18-8) stainless steel with a highly durable black electrophoretic coating, offering lifetime resistance against rust while providing a sleek, non-reflective matte finish that won't easily flake off UNIVERSAL #4 STEALTH FIT (ALL SCENARIOS): The #4 thread is ideal for micro-assemblies requiring a dark, seamless look. Choose short lengths (1/4" - 1/2") for PC chassis, speaker grilles, and thin plastic electronics; or extended lengths (up to 2") for mounting 3D printed brackets and deep dark-wood crafts SECURE CLAMPING & ANTI-STRIP DESIGN: Engineered with a flat-bottom Pan Head that distributes pressure evenly, preventing the screw from crushing delicate plastics or thin sheet metal. The sharp self-tapping threads ensure rapid bite, while the optimized #1 Phillips drive ensures precise engagement to eliminate cam-out INSTALLATION & ATTENTION TIPS: A standard #1 Phillips screwdriver is highly recommended for all #4 lengths. Warning: 304 stainless steel is softer than hardened carbon steel. You MUST pre-drill a properly sized pilot hole in wood or hard plastics, and NEVER use an impact driver to prevent snapping the screw head Pan head sheet metal screws have a round head and self tapping point. Pan head sheet metal screws, also called as pan head Sheet Metal Tek Screws or pan head Self Tapping Screws, are commonly used in indoor and outdoor applications. With special black treatments, the screws made of the finest 100% 304 stainless steel shows better corrosion resistance than 304 stainless steel screws without coating outside. Automobile, machinery, electronics, assembling, construction, manufacturing industry, indoor and outdoor.