The TR U-nut is a fastener composed of two flaps in clip form with two external raised thread forms. The design of this nut means that a double elastic force is exerted when tightened. This nut can be held in place manually when tightening. No special tools are required to mount U-nuts, and they can be assembled much more quickly and easily than conventional nuts. The self-locking feature means that costly operations such as tapping, welding or riveting can be avoided. It can also be used with fragile materials such as glass, plastic or enameled surfaces. In these cases the resilience of the nut avoids cracks or damage to the application area. This nut locks with tightening torques much lower than for standard nuts due its great resilience. It is normally mounted on the edge of a panel but it can also be used in a rectangular mounting hole in the middle of a panel. Thanks to the extremely wide range of Mikalor U-nuts, designers can chose amongst an infinite number of different dimensions, panel thicknesses and screw sizes. The fact that the U-nut allows slight adjustment within the mounting hole ensures correct alignment of the panels.