Injection device comprising an elongated body (1) with a hollow needle (8) at a distal end； a reservoir for an injection material to be delivered through the needle； a plunger (3) with a first force element (5) configured to provide an injection force to said injection material, and a distal element (10) attached to the distal end of the device thereby sealing a needle lumen, wherein the distal element comprises a tissue interface and a distal seal (11), and wherein the distal seal is penetrable by a distal tip of the needle by the application of pressure on a tissue surface with the distal end of the device, wherein the penetrated distal element becomes slidable on the needle to allow advancement of the needle into tissue, wherein the penetrated distal seal opens a path for flow or delivery of the injection material from the distal end of the needle.
