In the last trading session, U.S. stocks were mostly in the red as investors closely eyed the first presidential debate, the oil price movement ahead of the meeting between major oil producers and the turmoil in the European financial market following the Deutsche bank stock crash. Among the top ETFs, investors saw (SPY Quick QuoteSPY - Free Report) lose over 0.8%, (DIA Quick QuoteDIA - Free Report) shed over 0.9% and (QQQ Quick QuoteQQQ - Free Report) retreat about 0.9% on the day.

Two more specialized ETFs are worth noting in particular though as both saw trading volume that was far outside of normal. In fact, in the most recent trading session, both these funds experienced volume levels that were more than double their average. This could make these ETFs the ones to watch out for in the days ahead to see if this trend of extra interest continues:

: Volume 3.81 times average

This volatility ETF tracking the S&P 500 VIX Short-Term Futures Indexwas in focus yesterday as roughly 1.1 million shares moved hands compared with an average of roughly 300,800 shares. VIIX gained over 5.3% on the day.

The heightened uncertainty in the market regarding how the first presidential debate would go and the upheaval in the European financial market following the plunge in Deutsche bank shares put this volatility ETF in the spotlight. In the last one-month period, VIIX was down about 2%.

: Volume 3.60 times average

This small-cap India ETF was under the microscope on Monday as nearly 106,110 shares moved hands. This compares to an average trading volume of 29,440 shares and came as SCIF lost about 0.7% in the session. In the last one-month period, SCIF was up 5.6%. The fund has a Zacks ETF Rank #2 (Buy).

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