Long Left Right Arrow

Identified as the Long Left Right Arrow, this character acts as an extended horizontal stroke terminated by arrowheads on both ends. Within the Supplemental Arrows A block, it is categorized as a mathematical symbol and is usually read aloud as "if and only if" or "is equivalent to" when used in technical notation. It functions as a wider version of the standard bidirectional arrow, providing better visual balance in long equations or complex diagrams.

In practical writing, this symbol is primarily used in mathematical logic and set theory to denote material equivalence between two statements. It also appears frequently in chemistry to represent reversible reactions or chemical equilibrium where a long, clear divider is necessary. Outside of academics, digital designers sometimes use it in website navigation menus or user interface mockups to indicate a swiping motion or a reciprocal relationship between two interface elements.