The injection syringe which is particularly used for medical purposes. The syringe has a body, a piston which is disposed in the syringe body for displacement therein and an injection needle. The piston has at least two piston elements, 3 which are displaceable in relation to each other along the longitudinal...http://www.google.fr/patents/US5354285?utm_source=gb-gplus-shareBrevet US5354285 - Injection syringe
