This is a typical Royal Navy steam pinnace from the early 20th century. Steam pinnaces were the largest ship's boats of the time, and were capable of carrying light armament (in this case, a 3-pounder 47mm gun) and acting as picket boats to defend harbours and moored ships from torpedo boat attack.
The model is built from the Billing Boats kit which has a plank-on-bulkhead wooden hull and deck, with the superstructure and fittings being assembled from wood, plastic and metal parts. The kit is rather expensive (about £50-60 in the UK) but I had the luck to pick up a part-built one on eBay for around £20.
Billings' kit is, overall, quite accurate (compared to the plans in "Anatomy of the Ship: HMS Dreadnought") but is lacking in detail in some areas. I made some small scratchbuilt additions including the steering cable and pulleys which link the wheel to the rudder, along with handles on the hatches, glazing in the running lights, and portholes in the engine-room roof (the central white-painted steel structure). I also turned a new gun barrel from brass, as the kit part (moulded in two halves) was roughly moulded and nearly oval in shape! The crew figure is a George Turner Models metal casting. The kit suggests a blue paint scheme to represent an Admiral's Barge, but I painted mine black to represent a standard pinnace.