A blood collection needle assembly includes a holder body having a tube receiving chamber and a needle receiving chamber. A proximal needle is mounted to the holder body and projects into the tube receiving chamber. A distal needle is slidably mounted in alignment with the needle receiving chamber. A spring is provided to urge distal needle into the needle receiving chamber, and a trigger is provided for selectively permitting or preventing proximal movement of the distal needle. A transverse passage between the two needles is formed from a transparent material and provides indication of venus axis. The blood collection needle assembly is used to collect a sample of blood in a conventional manner. After collection of the blood, the trigger is actuated to release the distal needle and the spring propels the distal needle in a proximal direction for safe shielding within the needle receiving chamber of the holder body.

 
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