The caravan manufacturing started in Latorpsbruk, outside of Örebro, in 1964. It was marketed as Stjärnvagnen (the Star Wagon) and was, maybe to 97%, a copy of an SMV 10.


In the end of 1964 the AB Osby Pumpindustri (OPIO) took over the manufacturing. The first few caravans had the door on the left side, just like the SMV 10, because they were meant for traffic on the left side of the road, that Sweden had at the time. Later, during 1965, the design was changed with the door on the right side, to suite the coming change to drive on the right side. The Osby Pumpindustri main business was manufacturing of boat engines, branded Göta and Solo but they expanded their business by starting the caravan manufacturing. The caravan, that had a length of almost 4m, got the designation OPIO 600 and was a classic egg shaped design, with a wheel dimension of 9”. It is not certain but a guess is that 600 stands for 6m² floor area. A more modern designation could have been OPIO 390, since the length was about 3.9m. The caravan design was out dated at the time but it was popular and sold quite well.


In 1966 the model OPIO 500 L was added. Its length was about 3.1m. From the side view the OPIO 500 looked fairly egg shaped but the side walls were not arched, instead they were flat. It is a lot easier and cheaper to make flat walls, so the price tag could be fairly low. Of all OPIO models, it was only the OPIO 600 that had arched side walls.


In 1967 the models OPIO 400 L and OPIO 700 LA/LB was added. The OPIO 400 length was about 2.8m and the OPIO 700 length was about 4.2m. The OPIO 700 came in two versions, the 700 LA and the 700 LB, having different interior layouts.


In 1968 the OPIO 500 was discontinued. The OPIO 400 was stretched slightly, almost to the length that the OPIO 500 used to be. Chassis with 9” wheels was replaced by chassis with 13” wheels, from Peak in England. The OPIO 600 LP got an updated kitchen. The model OPIO 650 L was added. It was the same size as the OPIO 600 but having flat side walls and higher internal hight in the rear end of the caravan (i.e. like the OPIO 700). So, it had a more modern look and style than the OPIO 600.


In 1969 the OPIO 700 was discontinued. The OPIO 600 LP and the OPIO 650 LA/LC was the models that was manufactured.

In 1970 the AB Osby Pumpindustri was bankrupt. AB Götamotorer and the boat engine manufacturing was saved and is still in business in Osby town, as the Motorfabriken GÖTA (The Engine Factory GÖTA). Ronneby Husvagnar AB (ROHAB) in Kallinge, took over the caravan manufacturing and branded them Rohab-Opio. The model 670 was added. It was a version of the model 650.

In 1971 the model 600 was discontinued. The model 650 became the 660. The models 671 R and 771 LT were added. The model 771 was marked as having a length of 4.4m but it had the same chassis as the 660, the 670 and the 671. By tilting the front wall forwards, the caravan appeared larger but the floor was unaltered. This altogether, gave the caravan a different look.


In 1973 the models 660, 670 and 771 were discontinued. The model 671 was made in the versions 671 LP and 671 LC. The model 771 was replaced by the 773 and the 773 LT.

In 1974 also Ronneby Husvagnar AB was bankrupt. Österlens Husvagnar AB in Löderup, took over the caravan manufacturing but they also got financial troubles and after about a year the Rohab-Opio caravans disappeared from the scene.