This is a big rocker switch. The switching element is a industrial micro switch.

You will need:

• 2 pan head self tapping screws 2.2x10
• 2 pan head self tapping screws 2.2x12
• 2 pan head self tapping screws 2.2x5
• 2 round neodym magnets 5x2 
• 1 micro switch 20mm

You have to glue the magnets with super glue in the receptacles as seen in the cross section view. They have to face each other repellent.

Use PLA at least for the base. PET is too flexible.

have fun!