It looks like an XLR connector. You will need to confirm what type of connector you need for your battery. I searched Hitroad 36v battery charger, and i found the link below. I assume you have alreay tried that site since it was at the top of the search results. Be sure to look at all the details to confirm the one you purchase will be OK for your battery/bike controller. If you can't find a standard one to purchase there are ways to build your own which are safe.
HITTROAD E-Bike Battery Chargers from Powatechnic
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