BACK ZIP BOOTS Horse Full Grain Leather SB06DESCRIPTION GUIDI Shoes Collection. Back zip boots with a square shape and slim toe. The shoe last has been changed from the previous model and the basic specifications such as the compact toe and the finely finished shaft which holds the whole foot perfectly, have been finished sharper as a whole. The leather is horse leather and the heel is a single sole. This pair of back zip boots, which is a brand's iconic work, has a different look from [988].