NWT Maxi long straight party prom dress black & gray silk with snake print US 12

Maxi long straight dress in black & gray silk fabric with gorgeous black & gray phyton snake pattern print, designed by English brand Richards. Perfect dress for a formal summer event and also for prom party. Fully lined inside. Long zipper closure at its back. Personally purchased this dress in London UK but never used it and kept it clean with its plastic tag on it, in smoke free per free home. UK size 16 which fits US size 12. Please see all pictures for measurements. When laid flat, armpit to armpit is close to 21” inches wide & its waist is about 17” inches.