Cap Head Torx Machine Screws are also known as star drive screws they have a six-point star recess in the head that increases torque exertion prevets cam out and boosts fastener life. The torx drive allows for a higher torque to be exerted than a similarly sized conventional hex socket head without damaging the head and/or the tool. Torx head sizes are described using the capital letter "T" followed by a number ranging from T1 to T100. This product shares similiar specifications to the socket allen screw range Material / Coating: Stainless Steel A2-70 G304 is the most popular grade of stainless steel. It is aesthetically pleasing to the eye and very practical because of its excellent corrosion protection in most environments. Most products can be identified by the following markings: A2 A2-70 304 or G304. Stainless steels are largely non-magnetic but it is common for stainless steel fasteners to show a small degree of magnetism which is a result of work-hardening during the manufacturing process Can Stainless corrode?: Stainless steel is corrosion-resistant but not corrosion-proof and corrosion can occur if the material is installed or handled incorrectly. The use of tools and drills made from conventional steel during the installation of stainless steel fasteners may also lead to problems. Even the hardest of tools can produce debris that leaves minute steel particles on the stainless steel fastener surfaces or in pre-drilled holes. It is these particles that often rust when exposed to moisture or oxygen and can result in a stained or tarnished finish to the stainless steel material Thread Pitch (Metric): Pitch means the distance between the peaks of two threads along a screw bolt or fastener expressed in millimetres (mm). Used when referring to Metric parts. For example a thread pitch of 1.50mm means that the distance between one thread and the next is 1.50mm Fastener length: is generally measured from the point where the surface of the material will be when the fastener is installed to the end of the fastener. All material is advisory only and its use by anyone is entirely voluntary. Reliance on it for any purpose by anyone is at the sole risk of that person and Bolt and Nut Australia is not responsible for any loss claim or damages arising therefrom.