This power rubber is German-made and was co-developed by Michelin.
42.5 degrees sponge is mid-range between soft and hard, so dwell time is still there along with some firmness to allow serious power along with variation in loop spins.
Target Rubbers in brief:
Target Sound Version: 37.5 degree softest and spinny with click.
Target Force Versions: 42.5 and 45 degree mid hardness.
Target Ultim Versions: 47.5 and 50 degree hard sponge fastest versions.