... locked with the needle.And draw the needle in barrel .The plunger can be broken easily after draw ... uncomfortable when self-destruction starting,.5,Consist of :Barrel,Plunger with protect wing,Rubber stopper,Hypodermic Needle6,Don ... power to push the plunge to botton of barrel till locked .So there is no shake when ... in the muscle ,and no extra pain.The Barrel is transparent enough to help the user to ...