It represents 333,300 units of base currency.
In forex you trade currency pairs. The first currency is the base currency. The second currency is the quote currency AKA the counter currency.
- If you trade 100K EUR/USD this position has a face value worth 100,000 euros.
- If you trade 100K USD/JPY this position has a face value worth 100,000 US dollars.
In that case, consider trading only one micro lot (1000 units of base currency) per trade to start.
You may find this earlier discussion helpful: Pip value for 500 bucks on metatrader 4