A needle tip assembly for a pre-loaded syringe or a pen needle injection device, the needle tip assembly including a body comprising a double-ended needle and being installable and removable from the pre-loaded syringe or pen needle injection device. A needle cap is configured to cover a skin puncturing end of the double-ended needle and is removable to exposed the skin puncturing end. An outer safety member has a first portion that surrounds the body and a second portion that surrounds the skin puncturing end.