99 of 102 people found the following testimonial helpful.
Prima Auto Syringe
Posted By: MarkinTexas (GREENVILLE, TX) Jan 23, 2006
I have 3 of these and have used them on hundreds of cows and calves. I also ordered each of the other models available to compare. These by far are the easiest to use because: 1. they have a place to hook the gun up out of the way on the squeeze chute; 2. their handle is much more comfortable on the hand; 3. they have a better spring to reload the next shot; 4. they have a much better way of holding the needle and it is much easier to change than the other models; and 5. setting vaccine amount is much easier and stays where you put it. The only thing I wish the manufacturer would do is supply replacement O-rings for the barrel. After about 500 shots the o-ring starts to wear.