The pump volume/firing chamber volume, though, is a whopping 6mL. If that wasn't bad enough, the stream produced even suffers from drop-off, losing performance through the shot. Perhaps the first 3 or so mLs get out at full speed, then it tapers off to a dribble.
On the "bright" side, the blaster does work in "slam-fire" mode. Since this thing is so small and the pump volume so low, there is no notable lag when pumping.
However, another problem with this blaster's design shows up when going for refill. The cap on the reservoir has no hole and there seems to be no other inlet for air. Thus, as water is being drawn out of the reservoir, its internal pressure is dropping versus the outside. Thankfully (???), the reservoir is small that it does not end up collapsing due to the negative pressure, but this is definitely a design oversight.
The blaster looks nice and the grip is very comfortable, but I don't think many here will find much use in this blaster. Perhaps as a back-up for your back-up's back-up?

