The company was founded in 1932 by Hans Cohnen, initially specializing in glow plug repairs. Its product range quickly expanded to include hoses and fittings for the automotive industry. The company relocated its headquarters to Dillenburg during World War II. In the following decades, additional locations were added in Montabaur, Manston (UK), Chodov (Czech Republic), and Lipova (Romania). Today, with over 600 employees, COHLINE is a family-run specialist for pipe and hose systems in the fuel, cooling, oil supply, turbocharging, and hydraulics sectors. Its service portfolio includes the development of customized smart fluid systems made of metal, plastic, and elastomer using processes such as bending, soldering, welding, and spin welding. The company is certified according to IATF16949, ISO14001, ISO45001 and TISAX and supplies globally operating manufacturers in the automotive, commercial vehicle, construction and agricultural machinery industries.