$ProShares UltraPro QQQ ETF(TQQQ.US)$ Since TQQQ refers to NASDAQ100, it is important to understand the constituent stocks of the same index. The main stocks of TQQQ are the main stocks of the NASDAQ100 linked index.
The top 20 constituent stocks as of September 2021 are as follows.

TQQQ ( $ProShares UltraPro QQQ ETF(TQQQ.US)$) QQQ ( $Invesco QQQ Trust(QQQ.US)$Similarly, the price change of the NASDAQ100 index is three times more leveraged than the QQQ. If the index rises, you will get more profit than QQQ, but falling will cause huge losses. It can also be said that TQQQ is a high-risk and high-return commodity. There are few securities companies operating, which is different from QQQ.
Moreover, QQQ has differences in rates and total returns. The annual fee for QQQ is 0.2%, while the cost of TQQQ is 0.95%, about five times.
In addition, the total return will be about three times the difference with QQQ. A high return is fine when you make a profit, but a loss with high volatility will cause high risk and may be deeply rooted in the hearts of the people.