Abstract: Disposable medical syringe 10, consisting of a hollow syringe chamber 12, for receiving a piston 14, traversing a displaceable extendible path 16, in the chamber, a rod 18, axially coupled to one end of the piston 14, and at the other end to a thumb engaging surface 20, a stop member 22, in the hollow chamber 12, at a proximal end and adjacent to the rod 18 for terminating one end of the displaceable extendible path 16, a cap 30, securely but removably mounted at a distal end of the hollow chamber from the one end and having a tubular coupling 32, for receiving in frictional engagement a syringe needle 34, a supporting body for axially centering support of the needle within the hollow chamber and securely mounted to an inner end of the needle 34, a distal end of the needle 34, adapted for injection in a patient for serving to pass fluid received from the hollow chamber to pass into the patient, an annular projection 38 disposed about the tubular coupling 32, for latch-engaging the distal end of the needle the