2.5.8 When the GD&T specifies datum

2.5.8 When the GD&T specifies datum reference features without tolerance zone mobility modifiers, a single datum pin simulating Regardless of Material Boundary (RMB) is required and to be used for variable and attribute gaging 2.5.9 When the GD&T specifies datum reference features with Maximum Material Boundary (MMB) tolerance zone mobility modifiers, two datum pins need to be made with the option to change between them for different purpose. See Section 2.5.9.1 and 2.5.9.2 for its application. Deviation from these applications is allowed but must be approved by TSL Dimensional Engineering