In the last trading session, U.S. stocks ended lower driven by a technology sell-off. Among the top ETFs, (SPY Quick QuoteSPY - Free Report) and (DIA Quick QuoteDIA - Free Report) lost 0.5% and (QQQ Quick QuoteQQQ - Free Report) move lower by 1.4% 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:

(IDU Quick QuoteIDU - Free Report) : Volume 3.41 times average

This utilities ETF was under the microscope yesterday as nearly 211,000 shares moved hands. This compares with an average trading day of roughly 64,000 shares and came as IDU shed about 0.6% in the session.

The big move was prompted by the defensive investment amid turbulence. Being a low-beta sector, utility is relatively protected from large swings (ups and downs) in the stock market. IDU has added 0.6% in the past month and carries a Zacks ETF Rank #5 (Strong Sell) with a Medium risk outlook.

(KBWB Quick QuoteKBWB - Free Report) : Volume 2.97 times average

This bank ETF was in the spotlight yesterday as about 1.7 million shares moved hands compared with an average of 586,000 shares a day. We also saw some price movement as KBWB added 0.07% in the last session.

The movement can largely be blamed on a sharp rise in Treasury yields that has benefited stocks like those that we find in this ETF portfolio. KBWB is up 5.6% in a month’s time and has a Zacks ETF Rank #2 (Buy) with a High risk outlook.

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