SECTION 233319-DUCT SILENCERS

RNN: Outer casing shall be not less than ASTM A653/653M, 22 gauge, die-formed, type G60 galvanized lock former quality steel. Rectangular Elbow Silencers including models . EFN, ECN, EFP, ECP, EXFN, EXCN, EXFP, EXCP, and. ENN: Outer casing shall be not less than ASTM A653/653M, 22 gauge, die-formed, type G60 galvanized lock former quality steel ................
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