Eight milliliters. Official website of Guyuelongshan inquired that 500ml bottle cap of Guyuelongshan can hold 8ml wine. Zhejiang Guyuelongshan Shaoxing Wine Co., Ltd. is a leading enterprise in the yellow rice wine industry in China, one of the 520 key enterprises in China, the vice-chairman unit of china alcoholic drinks association, the chairman unit of china alcoholic drinks association Yellow Rice Wine Branch, and the top ten light industry enterprises in China (seventh place).