This technique targets demersal species. Horizontal opening is favoured. The goal is to cover a larger area than with a single trawl.
The rig can have 2, 3 or 4 warps, and there can be up to 4 trawls depending on the selected rig.
Trawls are made in Brezline for the bottom part and Breztop (or standard green polyethylene) for the upper part.
Groundrope rig (rockhoppers, rubber accessoires and washers for example) change depending on targeted species and the nature of the sea-bottom.