Torx Pan Head Machine Screws
6 Lobe Stainless Steel Machine Screws
Torx Pan Head Machine Screws feature a Pan Head and a Torx Drive, also referred to as 6 Lobe. Torx head machine screws are often used with nuts as well as driven into tapped holes. In practice, they tend to be mostly available in smaller sizes and the smaller sizes are referred to as screws, or less ambiguously as machine screws, although some kinds of machine screw can be referred to as stove bolts.
Torx Drive Screws are designed so the driver will not slip out of the fastener as will a Phillips drive, since the driver is not inherently centered on the fastener.) A benefit/disadvantage of non-typical fasteners (depending on your point of view) is that it can be more difficult for users of a device to disassemble it than if more-common head types were used. The Torx, or 6 Lobe Drive reduces the chance of fastener stripping, allowing for a higher torque installation.