Abstract: A retaining apparatus includes a short fold, a long fold, a tube connecting the short and long folds and forming a channel, and at least one enhanced engaging mechanism. The channel is approximately three hundred sixty degrees. The retaining apparatus is made of stainless steel. Each enhanced engaging mechanism includes a first bulge in the short fold, a first recess in the short fold, a second bulge in the long fold and a second recess in the long fold. The bulges and recesses correspond to each other. Each mechanism can be a female or male enhanced engaging mechanism. The first recess receives a portion of the second bulge, or the second recess receives a portion of the first bulge. The short and long folds are approximately parallel to each other. The height of the tube is bigger than the sum of the thicknesses of the short and long folds.