Stainless Steel A2-70 Hex Socket Screws with Semicircular Head for Wear-Resistant Applications

These metric machine screws offer a practical fastening solution where the properties of stainless steel are required. Designed with a semicircular pan head and an internal hexagon socket drive, they combine a relatively low-profile installed appearance with the positive torque transmission of a hex key. The specified A2-70 grade provides a defined level of mechanical strength and corrosion resistance, making these screws a candidate for assemblies exposed to moisture or requiring a degree of rust prevention. The whitewash surface treatment delivers a uniform, clean finish straight from the pack.

Features and Construction

This screw is defined by its material specification, head style, and drive type, which together determine its suitability for various projects.

Material and Build

The screw is constructed from stainless steel, specifically graded to A2-70. This designation is crucial; the 'A2' refers to the austenitic steel type, known for good corrosion resistance, while the '70' indicates a tensile strength of approximately 700 MPa. This combination makes it suitable for many general-purpose applications where resistance to rust and moderate strength are needed, though it is not recommended for highly corrosive environments like marine settings without further verification.

Size and Practical Fit

The source provides a specific size notation of 16*5.7mm, likely indicating a 16mm length and a 5.7mm head diameter or height. Crucially, these screws are offered in a wide range of thread size options. The available diameters include M2, M2.5, and M3, with numerous length variations under each (e.g., M2.510 denotes M2.5 diameter, 10mm length). This range allows for precise selection based on the thickness of the materials being joined and the required thread engagement.

Uses and Placement

The application is guided by the screw's material properties and mechanical design, fitting both hobbyist and professional contexts.

Event or Professional Use

In professional, workshop, or installation settings, these screws are applicable for assembling fixtures, machinery guards, or enclosures where stainless steel's resistance to staining and corrosion is beneficial. The hex socket drive allows for higher torque application compared to Phillips or slotted drives, reducing the risk of cam-out during installation in harder materials. The wear resistance mentioned in the source suggests suitability for parts that may experience friction or minor abrasion in service.

Everyday Home Use

For DIY and home improvement projects, these screws can be used for assembling outdoor furniture frames, fixing bathroom or kitchen fixtures, or any project where a cleaner, rust-resistant finish is preferred over standard steel screws. The semicircular head sits flush against the surface, providing a neat appearance. It is important for users to match the thread size (M2, M2.5, M3) to the correct pre-drilled pilot hole for a secure fit.

Benefits and Buying Value

The value of this product lies in its defined specifications and the practical advantages they deliver for appropriate tasks.

Reuse and Low Maintenance

Stainless steel A2-70 screws are less prone to seizing or corroding in place compared to uncoated steel, which can facilitate future disassembly and maintenance if required. Their inherent corrosion resistance reduces long-term maintenance concerns in damp environments, such as in garden sheds or garages, helping to preserve the integrity of the assembly over time.

Why Choose This Product

Choosing these screws is a decision based on material specification and fit. The clear A2-70 grade provides a known standard for corrosion resistance. The extensive size matrix (M2, M2.5, M3 with various lengths) allows for accurate purchasing to meet specific dimensional requirements. The combination of a hex drive for secure installation and a semicircular head for a finished look makes it a versatile option for visible fastenings where both performance and aesthetics are considered.