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) lost 0.4%, (DIA Quick QuoteDIA - Free Report) was off 0.4% and (QQQ Quick QuoteQQQ - Free Report) move lower by 1.2% 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:

(PEZ Quick QuotePEZ - Free Report) : Volume 8.48 times average

This consumer discretionary ETF was under the microscope yesterday as nearly 140,000 shares moved hands. This compares with an average trading day of roughly 19,000 shares and came as PEZ shed about 0.3% in the session.

The big move was prompted by solid manufacturing data, which bodes well for the consumer discretionary sector and can have a huge impact on stocks like those that we find in this ETF portfolio. PEZ has added 1.7% in the past month and carries a Zacks ETF Rank #2 (Buy) with a Medium risk outlook.

(RZV Quick QuoteRZV - Free Report) : Volume 7.19 times average

This small-cap value ETF was in the spotlight yesterday as about 51,700 shares moved hands compared with an average of 7,000 shares a day. We also saw some price movement as RZV added 0.7% in the last session. RZV is up 1.9% in a month’s time and has a Zacks ETF Rank #3 with a Medium risk outlook.

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