Lenz 1025 Gold...They are probably 20 years old...Anyways, I replace two engines today with brand new decoders, engine performance greatly improved with Factory Defaults. I just wanted to make sure that my settings were adequate in a few existing and I was getting full benefit of a speed curve. For several engines, I was setting Start Voltage at 3, Mid Voltage at 175, Max at 250. Results were acceptable.