This slab, together with its twin B 57, comes from the Monastery of Santa Maria Teodote or della Pusterla, currently the Episcopal Seminary of Pavia, where they constituted the presbyterial barrier, that is the enclosure that divided the part of the church reserved for the bishop and the clergy from that of the faithful. Critics assign it to the period of the Lombard king Liutprando (712-744). According to the typically aniconic taste of Lombard art, the subjects represented are plant and animal motifs: the central field houses a composition with the depiction of two sea monsters with lion heads, wings and anguiform tail, placed in front of a tree of life , an iconographic motif of Iranian-Persian tradition, which arrived in the West thanks to commercial and artistic exchanges with Constantinople. In the lower corners there are two small figures of dolphins. The two-dimensional articulation of the decorative elements prevails in the slab. Animals and the tree of life are characterized by sharp profiles. The series of coils in the tails of sea monsters, represented as superimposed disks, escapes this approach. The progressive anthropomorphic decorative loss towards a symbolic predilection of phytomorphic and zoomorphic elements, present in the slab, identifies the direction in which subsequent medieval art will develop.