The document discusses a self-loading concrete mixer that was produced in January 2016 and has been used for 1700 hours until April 2017. It describes how the unit was tested during the hottest summer months in Uzbekistan, with temperatures above 44 degrees, to evaluate the machine's cooling performance under extreme heat. Over 10-12 hours each day, the concrete mixer demonstrated good cooling quality by continuing to run effectively as the hydraulic oil temperature remained below 90 degrees.