Tail Design Break Force (TDBF): The minimum force that a new, wet, spliced mooring tail will break when tested according to MEG4 appendix B. Grommet Tail Design Break Force: TDBF in grommet configuration (x1.7 efficiency). Linear Density (LD): Linear density of line measured at reference load. Load Bearing Linear Density (LBLD): Linear density of load bearing member of the line, measured at reference load per CI-1500A.