Whip-it is the brand name of the whipped cream siphon that can be used, as well as the chargers themselves.
In the early days of my soda company, we used soda siphons (which look very similar to whipped cream siphons) to make soda at the Chattanooga Market. We got so many jokes about us using them to get high, even though we used CO2 as opposed to N2O. You don't get high by huffing carbon dioxide - you get dead.