These cables are used to connect one solar panel, also know as a solar module, to another.
Inter-Module, also called inter-connect, cables are 2-strand cables and are available in 26", 36", and 72" lengths.
The "MC" stands for "Multi-Contact" and these cables are also called "MC Connectors" and "MC Inter-connect" cables. They are specially designed for low-resistance and stability in widely varying conditions, such as seasonally extreme heat and cold. These connectors have numerous gold-plated, spring loaded "fingers" which assure that good contact is made under any condition, hence the term "multi-contact".
Each cable includes MC connector, 1/2" non-metallic cord connector with a #10AWG type 'USE' 600V rated outdoor black wire.