Screw & Bolt Head Styles
Head Styles Definitions - See Illustration Below
- Binding - undercut unless otherwise specified -not recommended for phillips recess
- Fillister - deep slot used for counter bored holes
- Flat Fillister - same as standard fillister without oval top
- Flat 82 degree - used where flush surface is desired
- Flat 100 degree - larger head than 82 degree used for thin metal soft plastic
- Flat Trim - same as 82 degree except diameter and countersink depth reduced
- Flat Undercut - standard 82 degree with lower 1/3 countersink removed for short screws
- Hexagon - manufactured as trim hex or indented hex
- Hex Washer - same as hexagon with washer section
- Oval - same as flat head with rounded surface for appearance
- Oval Undercut - similar to flat undercut with rounded surface
- Oval Trim - same as oval - smaller diameter and countersink
- Pan - recommended to replace round, truss binder
- Round - general purpose (see pan head)
- Round Countersunk - bolts only - similar to flat head with no driving recess
- Round Washer - same as round head with integral washer for bearing surface.
- Square Bolts - large bearing surface for wrench tightening
- Square Countersunk - for use on plow bolts
- Square w/Set Screw - recommended for high torque assembly
- Truss - similar to round head with larger diameter (see pan head)