Its description uses the terms "fighting knife" and "dagger", so I'd guess it looks like a short blade attached to a handle. Since more of its damage comes from industrial-strength acids than the knife itself, chances are the blade has a considerable amount of holes/grooves/whatever in it to allow the acids to get in the target's wounds, though they don't have to be big enough to be seen with the naked eye (and probably aren't). As it's manufactured by Paragon, their logo is probably on it somewhere. I'd also imagine the acid reservoir is contained in the handle (the blade itself wouldn't be able to store much) and that its bottom is removable to allow replenishing the acids.