US investors permitted
HADAX is a Chinese cryptocurrency exchange with low trading fees but with an odd selection of trading pairs. One of many other exchanges from China that you might be interested in if this exchange is not to your liking is BTCTrade.im.
We must also note that we could not find any information on the withdrawal fees charged by this exchange. This is potentially a risk for you as an investor.
We will prepare and publish a more detailed review on HADAX shortly.