The Technisub Conquest Booster is a very similar gun to the Mares Sten with a 40 mm tank. It was Technisub's next effort after the Ranger models which seemed to have big tanks but were actually rubberised shrouds that conferred a different shape to the usual grease gun appearance. Under that shroud was a smaller diameter tank and a higher compression ratio which was not what people wanted once they had used the Sten models and the very similar Cressi SL. I expect the same contractor made everyone's guns and the Conquest Booster appeared around the same time as the Mares Competition Line models in charcoal grey and lime green. The First Conquest Booster I saw shared those same colours. In later years the colour scheme changed as with most of the other companies to freshen up the model range.