An adapter is placed between the needle and a conventional fluid store, or medical line. The end of the adapter that connects to the needle assembly is formed to have a configuration that is complementary to that of the hub of the needle assembly, so that the adapter and the needle hub may be readily mated to each other. The other end of the adapter is formed to have another configuration, for example a conventional luer, that is readily connectable to a conventional fluid store, such as a syringe that has a conventional luer. The adapter is formed by inter-fitting two elements to effect an integral locking mechanism to prevent the uncoupling of the fluid store and the adapter, once they are securely coupled.
