This is the most underused piece of a mans wardrobe. The top button on a button down. When this is buttoned, the man is at his highest level of status, thus he has reached the penthouse button.
the term 'pengting' is used to say someone is very attractive or 'fit' as youths say. This is also known as being 'choong' or 'nang'. It can be used as just 'peng', but is seen as being slightly -cough- "cooler" to say 'ting' at the end.