For applications in stationary hydraulics KTR offer 10 different types of the high-power OAC oil/air cooler each producing the requested cooling power via heat exchangers in different sizes. Apart from the classical OAC there is the separate cooling unit OPC. In this case an independent cooling system with an integrated pump unit is concerned providing the cooler with oil via an independent circuit. As an option the unit can be equipped with an oil filter. In mobile hydraulics MMC combined coolers are used. In this case different media are comprised in a combined cooling system, the cooling element consisting of several individual elements. This allows to cool, for example, hydraulic oil, gear lubricant oil, charge air and cooling water in one single cooling system. The size of the individual cooling element is each adapted to the application, taking into account the thermal demands and the existing mounting space.