Not all needles are removable from the syringe. I use Terumo syringes and needles. The needles on Terumo syringes are screw on/off. It is always better to use a low guage needle somewhere around 18-20 for drawing the liquid from wherever (vial, amp) and then switch to either a 23 or 25 guage 1" - 1.5" needle. Hope this helps!

You can find Terumo brand syringes and needles at this site's sponsor - AR-R.