Hi SophieMy white reissue (2009) and red medium caviar flap (2007) have YKK zippers. YKK is used for special edition colors. Permanent line colors have EP zippers. There are also special edition colors with EP zippers as well, so it's up to Chanel.
Learn something new everyday. I see YKK on many items, not exclusive to luxury brands. Thanks for the info.YKK "Yoshida Kōgyō Kabushikigaisha" and EP "ever peak" are the suppliers for Chanel zippers! and "ever peak" EP also the supplier of the hardware .YKK is a Japanese company and EP is a Chinese one