L. Ducat LD Blue 100s is a carton of cigarettes containing 10 packs of 20 cigarettes each, for a total of 200 cigarettes. These are king-length 100mm cigarettes in the Blue variety, which represents a medium-strength blend in the LD lineup.

LD cigarettes (short for Liggett Ducat) were launched in 1999 and are produced under the control of Japan Tobacco International (JTI). The LD brand offers three main varieties — Blue, Red, and Silver — which differ in tobacco strength and tar levels. The Blue variety is positioned as the mid-range option in the lineup. The brand is marketed in the United States by JTI Liggett, based in Raleigh, North Carolina.