COMMON DRIVES
Combination Can be driven with either a slotted or Phillips driver.	Phillips Cross shape provides greater contact between screw and screwdriver for less slippage.	Slotted Single slot for driving with a standard slotted screwdriver.

TAMPER-RESISTANT DRIVES
	Hex Special hex shape with or without center pin is ideal for use anywhere vandalism or theft is a concern. One-Way Designed for use in permanent applications. Installs with a standard slotted screwdriver; requires special tool for removal. Spanner Unique design thwarts tampering, yet allows easy installation and removal with spanner tool.		Torx® Star-shaped drive with six rounded points allows maximum transfer of torque. Provides a high level of security without sacrificing accessibility. Torx Plus® Elliptical groove design maximizes engagement depth between driver and fastener. Ensures optimum torque transmission, and virtually eliminates camout. Tri-Groove Angled grooves cut into side of head provide excellent torque and maximum security.

HEAD TYPES
	Binding Has a rounded top that tapers around the edge and may have an undercut under the head. Button Features a domed top that protrudes above the fastening surface. Fillister (or Cheese) Features a relatively tall head with cylindrical sides; can be flat or rounded on top. Flat (or Countersunk) Has a conical head and a flat top; countersunk for a smooth, flush surface. Hex Head may be slotted for driving with a screwdriver or unslotted for driving with a socket or wrench.		Hex Washer Head allows tightening with screwdriver or wrench. Washer bottom of head provides secure mating of parts. Oval (or Raised Countersunk) Features a countersunk head with a low-profile, rounded top that protrudes slightly above the surface. Pan Disc with a chamfered outer edge and short cylindrical sides; has a slightly larger diameter than a round head. Round Has a more pronounced domed top than a button head. Truss Features an extra-wide, slightly rounded head with a low profile.

COMMON SCREW TYPES
	Machine General-purpose screws are typically used in noncritical applications. Most commonly used to fasten metal to metal, machine screws are designed to be inserted into a prethreaded hole or mated with a nut (in which case they may be called stove bolts). Sheet Metal Designed for quick entry into sheet metal, plastics, wood, fiberglass, aluminum, plywood, and hard rubber. They tap their own internal mating thread when inserted into a predrilled or prepunched pilot hole; the resulting fit has close to zero clearance for a strong hold. Thread-Cutting Self-tapping screws cut away and remove the surrounding material instead of displacing it. Create a zero-clearance fit that resists vibration and prevents loosening. • Used in harder, less pliable materials • Not recommended for applications requiring frequent assembly and disassembly		Thread-Rolling Self-tapping screws displace the surrounding material instead of removing it. Typically have higher drive and strip torque values than threadcutting screws. Not recommended for materials that crack under sustained loads. • Used in softer materials that can deform • For applications requiring frequent assembly and disassembly Thumb Featuring either a knurled or winged head type, thumb screws provide an ample gripping surface for applications requiring easy hand assembly and disassembly. Wood Form their own internal mating thread in wood or other resilient materials. They create a tight joint, but the screws can be removed easily without damage. Note: Predrilling is recommended, especially when used in hardwoods.