BOSTON ( TheStreet) -- ICOP Digital ( ICOP) was one of several stocks trading below $5 and moving on above-average volume Wednesday after the digital surveillance technology company said it received an initial order from the U.S. government.ICOP Digital said it has been selected by the U.S. Department of Homeland Security to outfit more than 100 vehicles with its in-car video systems. The order includes recording of mobile video/audio, wireless uploading, and live streaming video capability. Due to the security nature of the project, ICOP agreed not to release details of the project until the Department of Homeland Security releases its own press release. Shares of ICOP Digital jumped by 37 cents, or 16.2%, to $2.65. Volume topped 569,000 shares, compared to the average daily share volume of 20,000. Elsewhere, RMX Holdings ( RMX) shares continued to rally, jumping 11.1% to $3.11 Wednesday. RMX Holdings has surged more than 81% over the last three sessions after the company declared a special cash dividend of $1.32 per share of common stock payable on Aug. 23 to shareholders of record on Aug. 16. RMX said Tuesday that the New York Stock Exchange has contacted the company regarding the unusual market activity in accordance with its usual practices, but RMX said its policy is not to comment on unusual market activity or rumors. The company, formerly known as Ready Mix, provided ready-mix concrete products to the construction industry but has no active business operations after selling substantially all of its assets earlier this year. Volume topped 164,000 shares, compared to the average daily share volume of 35,000. SatCon Technology ( SATC) shares fell by 35 cents, or 9.3%, to $3.41 after the company said in a regulatory filing that NGP Energy Technology Partners exercised warrants to acquire nearly 8.1 million shares, requiring that SatCon issue about 5.31 million shares of its common stock to fully settle the warrants. SatCon added that NGP ETP subsequently sold the shares of common stock in a single block transaction. Volume topped 1.3 million shares an hour into Wednesday's session, compared to the average daily share volume of 1.37 million. BOS Better Online Solutions ( BOSC) rallied by 25 cents, or 22.9%, to $1.34 after the components-supply solutions company said it had a second-quarter net profit of $115,000, or 4 cents a share, swinging from a year-ago net loss of $2.4 million, or 95 cents a share. Revenue rose 30% from ayear ago to $10.4 million. BOS CEO Yuval Viner noted it was the company's first profit in several years. Viner also said BOS expects full-year revenue of $35 million now believe it will end the year with net profit. Volume topped 1 million shares, compared to the average daily share volume of 79,000. -- Written by Robert Holmes in Boston. Check out all of Wednesday's high-volume, under-$5 stocks at the Dollar Store. View the Dollar Store portfolio on StockPickr. Follow Robert Holmes on Twitter and become a fan of TheStreet.com on Facebook.