An injection device comprising an outer cover and a needle adjusting member for use with a syringe having a syringe body for receiving and administering a medicament via a needle: the outer cover being configured to be disposed on a syringe body of a syringe and the needle adjusting member being movably disposed on the outer cover such that said needle adjusting member is movably disposed along said syringe body between first and second positions, such that when said needle adjusting member is in said first position a needle of the syringe has a first effective length that is exposed and adapted to draw medicament into the syringe body, and when said needle adjusting member is in said second position said needle has a second effective length for injecting the medicament, said needle adjusting member comprising: a base having an opening for receiving said outer cover, said base being configured to be movable on said outer cover and along the syringe body between the first position in which the syringe needle has a first effective length that is exposed, and the second position proximal to the syringe needle in which the syringe needle has a second effective length, when the outer cover is disposed on a syringe body, the second effective length having a shorter exposed needle length than said first effective length to facilitate an injection and the first effective length is adapted to facilitate drawing medicament into the syringe body; the needle adjusting member further comprising: a flexible arm; and a needle adjusting member opening; wherein the outer cover has a first opening at a first end and a second opening at a second end, and said flexible arm is engageable with the first opening of the outer cover when said needle adjusting member is in said first position and the second opening of the outer cover when said needle adjusting member is in said second position; wherein the outer cover has a flexible arm at the second end thereof for engaging with said needle adjusting member opening when said needle adjusting member is in said second position and wherein, when said needle adjusting member is in the second position, said needle adjusting member is disposed more closely to an end of a syringe needle than when said needle adjusting member is in the first position to decrease the exposed needle length. a base having an opening for receiving said outer cover, said base being configured to be movable on said outer cover and along the syringe body between the first position in which the syringe needle has a first effective length that is exposed, and the second position proximal to the syringe needle in which the syringe needle has a second effective length, when the outer cover is disposed on a syringe body, the second effective length having a shorter exposed needle length than said first effective length to facilitate an injection and the first effective length is adapted to facilitate drawing medicament into the syringe body; the needle adjusting member further comprising: a flexible arm; and a needle adjusting member opening; a flexible arm; and a needle adjusting member opening; wherein the outer cover has a first opening at a first end and a second opening at a second end, and said flexible arm is engageable with the first opening of the outer cover when said needle adjusting member is in said first position and the second opening of the outer cover when said needle adjusting member is in said second position; wherein the outer cover has a flexible arm at the second end thereof for engaging with said needle adjusting member opening when said needle adjusting member is in said second position and wherein, when said needle adjusting member is in the second position, said needle adjusting member is disposed more closely to an end of a syringe needle than when said needle adjusting member is in the first position to decrease the exposed needle length.