Such types of vessels were called differently - naves, buses, keels, hooks. Distinguishing outward features of naves were highly raised posts, rounded in the bow part and straight in the stern part of vessels. We speak about vessels with a single mast. The use of a hinged rudder allowed making the most of side winds. Increasing of a vessel's draught and of its capacity assisted to exploit side winds. The bowsprit, shrouds with rat-lines and an anchor in the form close to an admiralty anchor appeared on the vessels of such a type.
Displacement of such a vessel slightly exceeded 200 t. Tack-clamps furnished by firm wood were used to lay tacks. The latter represented themselves strong cables as compared with a shkoat which was deprived of tackles. Stays and multiple rigging were moved to the stern.
Nave had asymmetrical extensions to the stern and bow superstructures. Perhaps they were done as additional rooms for knights who used such vessels at their crusades. The barrier of superstructures was ornamented with heraldic shields of knights.