Abstract: A loopback housing has an upper body portion and a lower body portion that are removably connected to one another. One of the body portions has a fiber opening to protect the optical fibers that are looped around for the fiber optic connector. The loopback housing also functions to remove and insert the fiber optic connector into an adapter, particularly in a high density application.

Abstract: A loopback housing has an upper body portion and a lower body portion that are removably connected to one another. One of the body portions has a fiber opening to protect the optical fibers that are looped around for the fiber optic connector. The loopback housing also functions to remove and insert the fiber optic connector into an adapter, particularly in a high density application.

Abstract: A friction stir welding system is provided that can afford a versatile and efficient welding operation. The friction stir welding spindle assembly can have a shoulder spindle and a pin spindle independently rotatable in relation to each other. The shoulder spindle and the pin spindle can be rotatably supported by a shoulder housing and a pin housing, respectively. The pin housing can be rotatably supported in the shoulder housing and adapted to be axially movable in relation to the same between a forward position and a retracted position. Additionally or alternative, the shoulder spindle and the pin spindle can each be provided with an adapter, which has a predetermined mounting surface for mounting a tool thereon.