Plastic Panel Fasteners are clips with shark like teeth to stop them pulling out.
Use a drill (larger size for harder wood) and make holes 4 to 5 cm apart into arm or area to take panel. Drill corresponding holes into panel, push fasteners through holes so that they protrude at the back of the panel. Tape over the tops at the front. Cover front of panel with padding and fabric. To fix, position fasteners over corresponding holes in arm. Knock the panel into place by placing a piece of wood over the panel and tapping gently with a mallet.