Extension of the product range for thermally highly strained engines. The HT + valve seat inserts complete the product portfolio of the successful HM- and HT valve seat insert range. HT is short for "high temperature resistance". The "plus" stands for the further development of the HT series. Against the backdrop of the current consumption and CO2 emission requirements, today's engine technologies are faced with challenges such as downsizing, turbo charging, gas operation as well as high engine outputs per litre. With the new HT + material the valve seat inserts satisfy the growing requirements of thermally highly strained engines.