Most of the H-1 and C-13 NMR signals of the 4-phenyl-1,2,3,4-tetrahydro-1-naphthyl end-group of polystyrene are assigned. An oligostyrene synthesized by thermally initiated "living" free-radical polymerization of styrene in the presence of 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) is used as a model compound. The TEMPO end-group is eliminated under formation of a benzophenone end-group prior to spectroscopical analysis. The tacticity of the backbone and probably the presence of the cis-and trans-stereoisomer result in a signal splitting of the end-group signals. The absence of a methyl end-group indicates that the starting radical is formed by H-abstraction from the Diels-Alder styrene dimer by TEMPO according to a mechanism proposed by Mead et al.