An injection device for injecting, the injection device comprising a housing having an interiorly facing wall with the wall having a plurality of ribs formed thereon, the ribs defining a channel extending therebetween, a plunger rod mountable within the housing and having at least one protrusion engageable within the channel, a cylindrical body, a spring mounted at a distal end of the housing with the spring being biased between the distal end and a needle hub, and a pusher rod raised such that pressure thereon from the plunger rod will cause the pusher rod to enter the cylindrical body, the pressure causing the spring to act on the needle hub to move the needle hub and the cylindrical body upwardly within the housing such that a needle is in an enclosed position within the housing and cannot be reused.