Mak Tai-kwong deftly takes a snake from one of the many drawers of a large brown cupboard labelled with the warning, 'poisonous snake' in Chinese characters. He cuts into the reptile's abdomen then squeezes out a little black organ - its gall bladder.
He repeats the process on two more snakes before pricking the three sacs with a knife to release the contents. The liquid is then mixed with two types of liquor (including snake wine, which is made by soaking steamed snake meat in alcohol and a secret blend of Chinese herbs), and Mak stirs it before offering the greenish-black liquid to his middle-aged customer, who downs it in one go.
'I've been taking [snake bile] for over 10 years,' the man says. 'It makes me vigorous.'
The use of snakes in Chinese remedies and seasonal cuisine goes back thousands of years. However, the practice has come under fire in the past decade over concerns that the creatures are being hunted and devoured to extinction.
Such worries haven't dented the enthusiasm of old-timers such as Mak, who has worked at She Wong Lam (literally Snake King Lam), a fresh snake meat purveyor in Sheung Wan, since 1948.
'I've been taking it since I was in my 40s, and I'm healthy and still fit for work,' he says. 'It strengthens qi and improves blood circulation, clears phlegm and wind from your body, both of which are said to promote illness in Chinese medicine. It also balances the endocrine system, speeds up the metabolism and slows ageing.'