Persons who purchase Met-Pro shares beginning today and prior to the effective time of the merger transactions—which are currently expected to occur between August 27, 2013 and August 29, 2013—will receive Merger Consideration consisting of all Stock Consideration in accordance with the proration procedures described in the merger agreement.Elections submitted prior to the August 23, 2013, 5:00 p.m., Eastern time, election deadline made pursuant to the notice of guaranteed delivery procedure require the delivery of Met-Pro common shares to American Stock Transfer & Trust Company, LLC, the exchange agent for the merger, by 5:00 p.m., Eastern time, on August 28, 2013, the third NASDAQ trading day after the election deadline. If the exchange agent does not receive the required stock certificates or book-entry transfer of shares by the guaranteed delivery deadline, the Met-Pro common shares subject to such elections will be treated as if no election was made, which would change the election results set forth above. After the final results of the election process are determined, the final merger consideration, and the allocation of the merger consideration, will be calculated in accordance with the merger agreement. Additional Information and Where to Find It In connection with the proposed merger, Met-Pro and CECO have filed with the SEC a joint proxy statement/prospectus, dated July 25, 2013, which contains important information, including detailed risk factors. This communication is not a substitute for the joint proxy statement/prospectus. Investors in Met-Pro or CECO are urged to read the joint proxy statement/prospectus and other relevant documents that have or will be filed by Met-Pro and CECO with the SEC. You may obtain a free copy of the joint proxy statement/prospectus and other documents that will be filed by Met-Pro and CECO with the SEC at the SEC's website, www.sec.gov, or by directing a request to Met-Pro Corporation, P.O. Box 144, Harleysville, Pennsylvania 19438, Attention: Investor Relations; or to CECO Environmental Corp., 4625 Red Bank Road, Suite 200, Cincinnati, Ohio 45227, Attention: Investor Relations. The joint proxy statement/prospectus has been mailed to Met-Pro and CECO shareholders. This communication shall not constitute an offer to sell or the solicitation of an offer to buy securities, nor shall there be any sale of securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of such jurisdiction.