Vỏ công tắc rocker inline (KCD1 & KCD11)

For 21x15mm and 15x10mm switches, which have many names and usually starts with KCD*.

Instead of using fasteners, glue, friction, compliant mechanism, etc. to bond the two parts, the walls slightly heated up and bent inwards. You can do this with a lighter (for a second or two) or heat gun, then push the wedge against a flat surface. See the last picture.