In general the so call 禮服 in HK are what we call Service Dress, there are only 3 type which is proper 禮服, the first is
the Red Ceremonial Dress, the next one is the Blue dress (no.1) and White Dress (no.3) and lastly the Mess Dess (both temperate and tropical versions). The fixing of buttons for the ones used in tmperate regions are just normal thread as they usually are dry cleaned. On the other hand the buttons fixed to the tropical region versions are removable to facilitate washing.
Regards
Kenneth
