In the last trading session, U.S. stocks saw rough trading, following the worst day in almost three months. Among the top ETFs, (SPY Quick QuoteSPY - Free Report) lost 0.8%, DIA shed 0.5% and (QQQ Quick QuoteQQQ - Free Report) moved 1.3% lower on the day.

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

(IWB Quick QuoteIWB - Free Report) : Volume 3.93 Times Average

This large-cap ETF was in the spotlight as around 1.3 million shares moved hands compared with an average 718,000 shares a day. We also saw some price movement as IWB plunged 1% in the last session.

The move was largely the result of declining stock market that has raised the opportunity to buy on the dip given the bullish fundamentals. This could have a big impact on large-cap stocks like the ones that we find in this ETF portfolio. IWB has risen 2.2% over the past month and has a Zacks ETF Rank #3 (Hold) with a Medium risk outlook.

(SPLV Quick QuoteSPLV - Free Report) : Volume 2.62 Times Average

This low-volatility ETF was under the microscope as nearly 7.5 million shares moved hands. This compares with an average trading volume of roughly 2.8 million shares and came as SPLV declined 0.7% in the last trading session.

The movement can largely be blamed on the nature of the low-volatility ETFs that have the potential to outpace the broader market in an uncertain environment, providing significant protection to the portfolio. SPLV has gained 0.4% in a month’s time and has a Zacks ETF Rank #2 (Buy) with a Medium risk outlook.

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