Complex sentence: Swiss sabres have single-edged, slightly curved blades which in the mid 16th century were set in regular sword hilts, including the variety of designs found there, with recurved quillions and/or rings and knuckle guards.
Split into simpler sentences: Swiss sabres have single-edged, slightly curved blades which in the mid 16th century were set in regular sword hilts. The hilts came in a variety of designs, with recurved quillions and/or rings and knuckle guards.