Certified Thermoplastics in Santa Clarita was acquired Monday by Ducommun Inc. for $30.5 million.

Established in 1978, Certified Thermoplastics specializes in precision extrusions and assemblies of engineered thermoplastic resins, compounds and alloys for commercial aerospace, defense, medical and industrial applications. Its customers include Boeing Co. and Airbus.

Aerospace manufacturer Ducommun said the buy, financed through an existing credit line, will be accretive to earnings within the first year following closing. Publicly traded Ducommun last year relocated headquarters from Los Angeles to Santa Ana.

Ducommun was established in 1849 and carries the distinction as California’s oldest continuously running company. It has worked on Boeing 737s since their inception in the 1960s.

Winston & Strawn LLP was Ducommun’s legal advisor. Houlihan Lokey served as financial advisor and Morgan Lewis & Bockius LLP served as legal advisor to Certified Thermoplastics.