NP Brass slot round headscrew,6BAx31.7mm

Imperial BA Thread - Nickel Plated Brass

Machine screws are fully threaded screws that are specifically designed to be used in pre-tapped holes or used with conforming nuts and washers in through holes. Machine screws are available in an array of configurations, materials, driver head types and sizes.
As their name implies, machine screws are used to fasten various components together in appliances, tools, machines, electronic devices, vehicles amongst a whole host of other objects. Machine screws are similar to a bolt but have a socket in the head which allows it to be turned with a screwdriver.

Standards

To BS57 & BS93