Fasteners – and Screws in particular – are manufactured with a variety of specialized head styles
- Hex Washer Head –The built-in washer provides a superior bearing surface. They come slotted or unslotted, with the latter being the most common. The length is measured from the base of the neck to the top of the head.
- Pan Head – A Phillips or square drive head with a low profile. The length is measured from the base of the neck to the top of the head.
- Flat Head — This countersunk head dips into the wood for a flush finish. The length is measured from the top of the head.
- Oval Head — A countersunk base with an oval on top delivers a polished look, similar to a flat head. The height of the head is used to determine the length.
- Flat Head Reamer – A flat-top and Phillips drive ream wood and then cut steel in one action with a flat head reamer. Wings ream clearing holes in thick layers of low-density materials to prevent thread engagement. The wings fall off, and the threads usually engage when the point penetrates the metal beneath. The height of the head is used to determine the length.
- Round Washer Head — These have a round head with a Phillips drive, similar to HWH. They are also known as either Metal Lath or K-Lath and modified.
- Truss Screws – Truss Screws are measured from the underside of the head.
- Wafer Head – A Wafer Head is also known as ply metal because it may join plywood and metal. The big wafer head has a broad bearing surface and digs into the plywood. The height of the head is used to determine the length.
- Drywall Bugle Head – Drywall Bugle Heads are used to secure drywall to metal studs (0.105′′). The height of the head is used to determine the length.
- Pan Framing – A Phillips drive stud-framing screw used to fasten a stud to a track. The length is measured from the base of the neck to the top of the head.
- Pancake Head – A head with a low profile and a big bearing surface. The length is measured from the base of the neck to the top of the head.
- Square Trim–This model has a square drive and a smaller head for confined places. The length is measured from the base of the neck to the top of the head.