This is an ALERT issued February 16, 2004 by the U.S. Coast Guard Office of Boating Safety:

A defective opening mechanism in some 12-gauge plastic flare guns manufactured by Olin (now Orion Safety Products) prior to 2000 may not open wide enough to accept a flare cartridge. Guns with a modification to correct the possible problem are marked with U.S. Coast Guard approval code
160 028//12/1. Boaters with older flare guns should check the operation of the opening mechanism now and at the start of each boating season. If the breech will not open wide enough to accept a cartridge, the gun should be sent back for a replacement. Send defective guns to: ORION SAFETY PRODUCTS, MARINE DIVISION, 3157N. 500W, PERU, IN 46970; 1-800-851-5260.