The electrical outlet and power plug type M are exclusive to South Africa, Swaziland, and Lesotho.
The Type M plug looks like the type D Indian plug but differs in dimension. The plug is rated 15 amp and has three pins arranged in a triangular pattern.
The line and neutral pins each have a length of 18.4 mm and are 25.4 mm apart from their center. The center earth pin has a diameter of 8.7 mm, and a length of 28.6 mm.
The grounding pin, and the middle of the imaginary line connecting the line and neutral pins, have a center-to-center distance of 28.6 mm.
The South African type M plugs has insulated sleeves on the pins, preventing electrocution when plugged halfway.
The plug is often preferred to other plugs for large appliances in several countries. For example, India uses the type D plug and the Type M plug for large appliances.
Some sockets in India can accommodate both the type D and M plugs. In the United Arab Emirates (UAE), and Israel, the Type M plug is used for washing machines and air conditioning circuits.
Theatre installations in the United Kingdom feature type M plug, though there’s a push to replace it with industrial blue and white CEE plugs.
Type M plugs, though widely used in South Africa, will soon be obsolete in the country. This is a result of the fact that the type N plug was made the standard plug in the country in 2013.
It became mandatory for new buildings to install at least one type N outlet, beginning in 2018.
This is surprising since it defeats logic for the government to enact policy that will lead to the slow adoption of a safer and new standard plug.
At the pace with which South Africa’s government policy warrants buildings to make use of the type N plug (SANS 164-1), the South African Bureau of Standards (SABS) believe it could take as much half a century, or two decades, if adoption is exceedingly faster than the government policy makes it, for the type N to reign supreme as the standard plug in the country.