The zip-fastener of a mouth softened into what, in view of his next words, I correctly interpreted in advance as being a nostalgic smile.    From Wordnik.com.  [When Eight Bells Toll]

It was, Bradley told himself, very much like watching a zip-fastener being pulled open - except that the teeth of the zipper had the most extraordinary shapes.    From Wordnik.com.  [The Ghost from the Grand Banks]

He was a short, powerfully built character, fifty-five I would have guessed, with a heavily-tanned jowled face, close-cropped iron-grey hair with tufted eyebrows to match, long straight nose and a mouth that looked as if it had been closed with a zip-fastener.    From Wordnik.com.  [When Eight Bells Toll]

Thanks to the 'zip-fastener' bonding of the nano-structure, the effects of abrasion on the insert are minimal and any tendency for 'thermal comb' cracks to develop are resisted.    From Wordnik.com.  [Manufacturingtalk - manufacturing industry news] Reference