As the title suggests, this socket is required when removing the factory 54mm nut on the flywheel/flexplate on a Mazda rotary engine.
This is a 3/4" drive socket, supplied also with a 1/2" adapter for use with both 3/4" and 1/2" ratchets or air/cordless tools.
Made out of durable thick wall CrMo steel, these are designed to last an eternity.