These syringes are of the disposable type. They are made of plastic with an NBR stopper. The needles come with a plastic cap for storage between uses. They may be used multiple times for various applications. Due to the large gauge/size of the filling needle, these syringes work well with viscous liquids.The tips on the needles are blunt and flat so they cannot pierce skin. The needles are non-sterile. They may not be used for injection or any medical purposes.