Like their predecessors, this latest series of vessels are 29.50m in length overall with a beam of 11m and maximum draft of 5.13m.

Construction of the rugged, welded steel, hulls and all major steelwork was sub-contracted to the Usti shipyard in the Czech Republic.

The completed hulls were then towed to Antwerp to be fitted out by SKB. Hull design and dimensions have been influenced by the vessels employment that is almost exclusively centred on shiphandling within Antwerp's very large enclosed docks.

In all three vessels, power is supplied by two ABC 8 cylinder MDZC diesel main engines, each rated at 1945kW (2643bhp) at 100rev/min. Power is transmitted to Voith Schneider type 28 GII 210 cycloidal propulsion units via Voith Turbo-couplings. This propulsion system gives the tugs a static bollard pull of 55 tonnes and a free running speed of 13.7 knots.

The tug fleet of the Antwerp port authority rarely venture outside the enclosed dock system and have in the past carried a minimum of navigational and seagoing equipment. Tug no.20 is still a relatively simple vessel but unlike its predecessors is fitted with a normal mast and a full set of lights to meet normal maritime regulations. The wheelhouse is also more compact and workmanlike than in the previous generation of vessels.

Accommodation comprises three cabins, a mess room and the usual sanitary facilities but is orientated around crews shift working from a single base ashore. On deck, there is an unusual arrangement of two single drum Brusselle hydraulic towing winches, one on the centreline aft and the other set at 45º but both serving a single 'staple' type towing fairlead.

Each winch has a line pull of 20 tonnes at 10m/minute.