Strip for retaining two extrusions in selected position

Mechanism for attaching a first member to a second member comprising:

• a pair of substantially rigid walls integrally formed on the second member defining a first channel therebetween, said channel having a serrated interior surface;
• a T-shaped attaching strip of substantially resilient material having a head portion at one end and a stem portion extending perpendicularly from said head portion, said stem portion having a relieved area to form a narrow neck portion at its other end with a transversely disposed portion mounted on the end of said neck portion;
• said stem portion being of a width substantially corresponding to the width of said channel;
• said first member having a pair of normally extending parallel wall members integrally formed along one of its sides to define a second channel for receiving the head portion therein;
• a flange on the free end of each wall member overlying the head portion within the second channel to retain the attaching strip therewithin;
• said transversely disposed portion being of a width slightly greater than the thickness of said stem portion and said first channel whereby when the first and second members are moved with predetermined force toward each other, the projecting stem portion enters into said serrated channel, in which position the side edges of the transverse strip portion grip the sides of the serrated channel and thereby restrain said first and second members against separation;
• the sides of said transverse strip portion being compressed into the relieved area of said narrow neck portion during insertion of said transverse strip portion into said serrated channel.