42mm is a standard socket. If you mean "what SAE socket fits," none of them do. BTW, what are you trying to get off that's got a nut that big on it?
A 27mm socket is typically a standard size used for 1-inch drive socket wrenches. You would need a 1-inch drive socket to fit a 27mm bolt or nut.
The standard length of a presta valve is typically 42mm.
The standard presta valve size for bicycle inner tubes is 42mm.
It is: 42mm = 4.2cm
The part of the tooth that fits into the socket of the jaw(mandible) or maxilla(for upper teeth) is the "root" of the tooth.
The standard width of an electric guitar neck is typically around 1.65 inches (42mm) at the nut, where the neck meets the headstock.
Fits socket 7 boards.
No, you cannot use a metrc socket on a standard socket wrench. These are two different systems of measurement and are not interchangeable.
Socket
Any battery socket that it fits.
The BPR6ES spark plug typically requires a 5/8-inch (16mm) socket for installation and removal. This size is standard for many automotive spark plugs. Ensure you have a spark plug socket with a rubber insert or magnet to help secure the plug during installation.
Spark plugs use SAE and not Metric. The one that fits it is the one that fits it.