Gray, very hard. Birch handles.
The Natural Rubber Series solves the two biggest problems most players have with rubber mallets: weight and tone. After years of research, we were able to find a way to keep the weight of the four models within one-tenth of an ounce of one another, so changing hardnesses does not mean changing weights. The Natural Rubber Series is also very useful on the many small bells, wood blocks and other idiophones of the percussion section.