Mitsubishi Chemical Diamana RB Wood Shaft Model Flex:63 R straight and as consistent possible bottom straight and as consistent possible Tip stiffness and torque are further controlled through the use of 40 ton carbon fiber in the shaft's construction Diamana™ RB was engineered to promote ease of launch while also maintaining control down field Diamana™ RB (Red Board) – the third profile in the most recent generation – is designed with all the traditional branding that made Diamana so beloved – including a return to the original 53 63 73 83 weight class designations – and all the engineering prowess and material innovation that made the brand dominant on tour