A sterile, micro-cutting device that is attached to a vitrectomy system handpiece for insertion into the eye, in order to remove (nibble away) the vitreous humour (the jelly-like substance that fills the centre of the eye) during ophthalmic surgery. The handpiece converts an energy (e.g., ultrasonic, piezoelectric) produced by a system generator into a mechanical oscillating-cutting action applied by this knife-like device. This is a single-use device.