The Ultimate Martial Arts Board design is similar to the size and feel of a real wooden board. It is constructed of super tough nylon to provide unbeatable strength and durability. Each board consists of two identical halves that snap together easily with our unique, patented hinge. The Ultimate Martial Arts Board will provide thousands of consistent breaks, no matter what your level of expertise! Over 100 Million breaks since 1998 More consistent than wood Colour-coded in 7 strengths Stackable for power braking Rounded edges, rubber backed Safer and less costly than wood Satisfaction guaranteed Colour code Approx. Resistance White 0.3" wood strip Yellow 0.5" wood strip Orange 0.7" wood strip Green 0.9" wood strip Blue 1.25" wood strip Brown 1.50" wood strip Black 2.25" wood strip