Rotary Injection Moulding Machines either with 48 or with 96 stations, with twin cavities mould-holders. The main technical features of the two models are the injection units, screw/piston type with electric motor drive, two and four respectively, and located horizontally in axis with the moulds, and the rotary table with one or two sets of 48 mould-holders. On each injection phase the Roto T2/48 produces two stoppers while the Roto T4/48 makes four; the machines may produce at the same time either cylindrical or T-shaped stoppers and, respectively, with two or four different materials/colours. Both machines may run with a cycle time of 1,8 / 2,2 seconds, thus granting an output of 3.000/4.000 pieces/hour with Roto T2/48 and 6.000/8.000 pieces/hour for the Roto T4/48. The injection is assisted via an accumulator which is housed in the base of the machine. The mould-holders are equipped with cooling circuit by coolant liquid and the mould opening is made using a special linear-rotary pneumatic device. The use of this Opening System allows the machine to be fitted with a manipulator for automatic feeding of inserts or for transferring the first moulded item to the adjacent cavity, in order to produce two colour stoppers automatically. The mouldings are pneumatically ejected from the cavities. The rotary table has an insulated protection, to avoid condensation on the moulds. The weight tolerance of the stoppers is +/- 0,1 gr. And the sprue, which is recoverable; weights only 0,12/0,14gr. per cavity. The machine operation is controlled via a PC/Touch-Screen system displaying all process parameters, alarms and Data memories. Presma software is prearranged for modem remote assistance.