I read some posts about this but its still not too clear for me. I want to start my first cycle soon and i want to change needles from the withdrawal to the injection. can i buy a 3 or 5cc syringe and then like some 21g needles for withdrawal and then some 23g for injections and are they guaranteed to fit the syringe or do certain needles fit certain syringes or all they all universal?
thanks for the help.