This allows you to change the focus of the lens of your C270 without disassembling it.
Unscrew the camera and break loose the lens. Google that up.
While disassembled take the plastic piece (the one with screws) and drill the camera hole with 11mm drill.
Assemble the camera back and glue the printed part to the lens. If you can't turn the lens counter-clockwise easily as far as you would like, just unscrew the case screws a little bit more.