In the last trading session, U.S. stocks saw mixed trading due to lack of new information from the Fed minutes. Among the top ETFs, investors saw (SPY Quick QuoteSPY - Free Report) and (DIA Quick QuoteDIA - Free Report) gain 0.1%, and (QQQ Quick QuoteQQQ - Free Report) move lower by 0.1% 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:

(IAT Quick QuoteIAT - Free Report) : Volume 5.82 times average

This bank ETF was in the spotlight yesterday as more than 826,000 shares moved hands compared with an average of roughly 150,000 shares a day. We also saw some price movement as IAT lost nearly 0.06% in the last session.

The movement can largely be the cause of rate hike speculations in December that would bolster bank margins and may have a big impact on the sector’s stocks like what we find in this ETF portfolio. IAT was up 0.4% in the past one month and has a Zacks ETF Rank of 3 or ‘Hold’ rating with a High risk outlook.

(BBH Quick QuoteBBH - Free Report) : Volume 3.54 times average

This biotech ETF has also been hogging the limelight as around 237,000 shares moved hands on October 12. This compares with an average trading day of around 69,000 shares and came as BBH shed 2.1% in the session.

The big move was largely the result of a crash in share price of Genomic sequencing company Illumina following its slashed revenue guidance. In the past one-month period, BBH was down 7.3% and has a Zacks ETF Rank of 3 with a High risk outlook.

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