Hydrocompatibility -, Hydrocompatible materials flow readily over the surface of the teeth and along preparation margins, making it possible to capture the details required for an accurate impression. Thixotropy – , They flow over the surfaces they are positioned on and do not run once they have been positioned in the patient mouth. High tear resistance, At least 99% elastic recovery, Ideal working time/setting time ratio, Long working time, Shorter permanence in the oral cavity, Different colours according to the viscosity, Available in tubes also