In the last trading session, U.S. stocks were mostly in the red thanks mainly to a rout in the tech space. Among the top ETFs, investors saw SPY losing about 1.6%, DIA shedding about 1.5% and QQQ move lower by 3.2% on the day.

Two more specialized ETFs are also worth watching 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 of the last trading session. This could make these ETFs ones to watch out for in the days ahead to see if this trend of extra-interest continues.

DOL : Volume 3.81 times average

This international large-cap dividend ETF was in focus yesterday as nearly 124,170 shares moved hands compared with an average of roughly 32, 600 shares a day. The fund lost about 0.2% in the last trading session and was down about 2.3% in the last one month.

IMLP : Volume 2.82 times average

This MLP ETF was under the microscope yesterday as about 20,000 shares changed hands. This compares with the average trading volume of around 7,000 shares and came as IMLP gained about 0.5% in the session. The fund has probably gained on optimism in the oil patch and demand for higher yield amid relative low benchmark U.S. treasury yields. The fund has lost about 10% in the last one month.

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