The Norwegian Tjeld-class vessels were used as motor torpedo boats (motortorpedobåt). They measured 80 ft 5 in long (24.5 m), with a beam of 24 ft 7 in (7.5 m) and a draught of 6 ft 11 in (2.1 m). They could reach a top speed of 45 knots and were armed with a 20mm Rheinmettal gun forward, a 40mm single Bofors aft and four 21 in (533 mm) torpedo tubes. The boats were built and commissioned in two groups. The first group of twelve were launched between 1959 and 1960, and commissioned in 1960-1962. A second group of eight vessels were launched 1962-63 and commissioned 1963-66. The twenty boats remained in service until the late 1970s and eventually were all disposed of by 1995. One vessel, Skrei (P380), was transferred to the Royal Norwegian Navy Museum for preservation as a museum ship.

The United States Navy ordered 22 vessels, built to the Norwegian design but with different armament. Known as the Nasty class, they were to be utilized as fast patrol boats employed by special forces for clandestine operations along the coast of North Vietnam. The torpedo tubes were removed and the gun armament comprised of a single 40 mm Bofors, two 20 mm guns and a piggyback 81 mm mortar/0.50 machine gun. After an initial order of two vessels in 1962 the USN ordered a further 14 in 1966 with an agreement for an additional six to be built under license in the United States by John Trumpy & Sons of Annapolis. All vessels saw action in the Vietnam War, with six being lost in action. However, at the end of the conflict all were disposed of except for PTF 17, which is preserved at the Buffalo and Erie County Naval & Military Park.

The Hellenic Navy ordered six vessels in 1965. Referred to as the Tjeld or Improved Nasty type patrol boats, they were identical to the Norwegian boats, but with two single 40mm Bofors, with one replacing the 20mm gun. The Greek boats remained in service until the 1980s, before being placed in reserve. All were disposed of by 1995. 

The West German Nasty class, also known as the Hugin class, were two fast patrol boats built for the post-war West German Navy and identical to the Norwegian vessels. They were purchased in the 1960s for evaluation purposes, however they were transferred to Turkey in 1964. The two boats served the Turkish Navy until stricken in 1973.

Most for the rafts contain the different weapons for the various fits. There are a variety of single 40mm Bofors mounts, again depending on which version you are planning to build. Some are fully printed and just need to be removed from the raft, while some others require the gun to be attached to the base and at least one of those appears to have a fully assembled version included. The Bofors has the ring bases printed next to them when applicable. Another raft has four 20mm Oerlikons, which appear to be well done. There is also a raft with the four torpedo tubes, with the tips of the torpedoes separate to attach as caps. A 3D printed torpedo is also included if you wish to display the model firing out of the tube. This is a very nice touch.

The remaining rafts provide various fittings and detail parts. These include rudders and propellers, masts, jack and ensign staffs, two types of radars, vents, hatches, storage baskets, ammo lockers, raft, anchor with chain, life rings, life raft canisters oxygen tanks and what appear to be floats (they look like tiny figs). One set of parts I did notice are the stanchions for the safety railing. Again, what you use will depend on which version of the vessel you will build. 

As mentioned above, a nice base with two pedestals that are also 3D printed are provided to display the full hull model if you so wish.

The third page has photos of a Greek, US and Norwegian boat which I guess are supposed to help with assembly but they could be clearer. The final page has two assembly diagrams showing the placement of most of the remaining parts, but again somewhat confusing and could be more specific as to what parts go with what version. No guidance on painting of decal placement is provided. The modeler will need to search the Internet for photos of Tjeld and Nasty class boats to help with your build. A good resource is the PTF-Nasty website (https://ptfnasty.com/index.htm). While it focuses on USN vessels fighting in Vietnam, it does have some information on the boats in the other navies.