A petite robusto has the same ring gauge as a robusto but is shorter: usually about 4 to 4½ inches long with a 48–52 ring gauge. The names vary. Some companies call the same size a short robusto, and some petite robustos are thicker.
The advantage is time. You get a thick cigar with room for ligero in the center, in a size that suits a short break. The disadvantage is that there is less length for the smoke to cool and for the flavor to develop as it burns.
It is a parejo. Compare the petit corona (a similar length with a thinner ring gauge) and the full-length robusto. Full guide: robusto guide.