Relations are used to define attributes such as tangency, parallelism, perpendicularity, and concentricity. Many castles naturally combined elements of both concentricity and linearity. Two common specifications for NMR tubes are concentricity and camber. The preservation of concentricity between the turning and grinding operations is crucial for quality work. A small section of the tip of the dead center is retained to ensure concentricity. Multiple blades allow the feed rate to double and can hold a closer concentricity. The intermediate gear was strengthened and concentricity improved. Concentricity tolerances affect the fiber, fiber core, and connector body.