Type L vs. Type M

Type L, Italy's standard, uses three round pins in a straight line rather than a triangle, in two incompatible sizes (10A and 16A). Chile and Uruguay use the same physical design, though no independently confirmed national standard document defines it in either country.

Type M is South Africa's large-pin standard -- the 15A variant of the same BS 546 family that produces Type D at 5A. The two share a triangular 3-round-pin layout and standard lineage but use different pin sizes, so they are not physically interchangeable.