The Shange shunt was a device invented in 2300 by an engineer named Shange. The Shange shunt was used to speed up plasma flow reaction time, and to make system flaws easier to diagnose. By the mid 24th century, the Shange shunt came to be considered a vitally necessary component of a starship's impulse engine, though older vessels, such as the USS Hathaway, proved able to function without the unit. (SCE eBook: Many Splendors)