710 is a number the scene uses as shorthand for concentrates. The reason is a visual trick: write it on a display, turn it upside down and it reads oil.
Hence the date too. 10 July (7/10) is the day events, sales and meet-ups happen around concentrates — the counterpart to 420, just aimed at this part of the scene instead of at flower.
Where you will meet it: in product names (710 tool, 710 kit), in hashtags and in what events get called. As a label for a specific thing it does not work — it is shorthand for a whole category.
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