Definition: Antiperistaltic, also known as an antiperistatic device or a brakeless valve, is a type of mechanical device that prevents fluid from flowing past a point where it would otherwise flow. It is commonly used in hydraulic systems to prevent excessive pressure build-up and ensure safe operation. This mechanism works by reducing the flow rate of fluid through a small opening orifice. The result is an increase in resistance or friction, which limits the amount of fluid that can flow past the opening,