A preloaded injector for storing and injecting hydrophobic intra ocular lenses (IOL) comprises a plunger (2), an injector body (12), an adapter (16), a rotatable member (18), a cartridge (20) with a nozzle tube (22) and a stopper (26). The rotatable member (18) is provided around the cartridge (20) for setting the cartridge (20) from an open position to a closed position. The rotatable member (18) is furnished with a portion interfering with a portion of the stopper (26) keeping the stopper (26) irremovable in its first position but releasing the stopper (26) in its second position.