Abstract: A catheter assembly having a catheter of flexible plastic tubing secured at one end to a catheter hub, a hollow adaptor body with a distal end for fluid tight connection to the catheter hub and in fluid communication therewith. The proximal end of the adaptor body includes a self closing elastomeric gasket valve member. An introducer needle is provided proportioned to extend through the catheter, hub and tubing for penetration of a patient's vein for introducing the catheter into the vein. The proximal end of the needle is secured to a plastic collar having proximal and distal ends and dogs at the proximal end for limiting slidable movement within a hollow cylindrical container. A sealable gasket closure at the distal end of the container safely encloses the needle within the container upon withdrawal of the needle. The assembly further includes a curved plastic transparent tube having a filter valve therein extending from the proximal end of the collar for sighting flashback.