An M5 screw is a metric screw with a nominal outer diameter of 5 millimeters. The "M" stands for metric, and the number following it (5 in this case) indicates the major diameter of the screw thread in millimeters. The typical thread pitch (distance between threads) for an M5 screw is 0.8 mm, which is considered the coarse thread. M5 screws are commonly used in engineering and mechanical applications and can come in various types such as hex bolts, socket head cap screws, button head screws, and more, all fitting an M5 nut and washer.
Key Characteristics of an M5 Screw:
- Diameter: 5 mm major diameter
- Thread Pitch: Usually 0.8 mm (coarse thread)
- Common Head Types: Hex, socket head, button head, flat head
- Drive Sizes: Varies depending on head type (e.g., 4 mm hex for socket head cap screws)
- Fits: M5 nuts and washers
- Length: Variable, specified as part of the screw designation (e.g., M5 x 0.8 x 9 mm)
Common uses:
- Furniture assembly
- Electronics housings
- Bicycles and automotive components
- General machinery fastening
M5 screws are used worldwide in many applications and standardized under ISO metric screw thread standards. The "M" designation helps distinguish it from other sizing systems like imperial or unified threads. Occasionally, M5 screws are very close in size to 10-32 screws in imperial units but are not interchangeable despite similar appearance.
If screw length or tolerance class is specified (e.g., M5 x 0.8-9), the length would be given in millimeters (9 mm in this case), and tolerance classes indicate thread tightness or fit quality.
