Wow! Now I understand why it's so effective. It's not just a syringe with a simple piston, but the real pneumatic pump! So sad there is no information on its construction. I'd be convinced to get one much earlier seeing that some real physics is involved .

JIM, I think the cut off syringe will work better than sucking by mouth, but its hard edges may damage the skin severely. I'm going to buy Sawyer today, and also I have some plastic syringes at work. I'll try to measure the difference in suction.