Airsoft Innovations is one of the few airsoft manufacturers based in Canada. They are widely known for their propane adaptors, as well as their tornado grenade.
In 2008, AI released their Tornado Grenade. It is widely accepted as the first skirmish usable airsoft grenade. A bit later, a spoon kit was released for the original tornado. At SHOT show 2010, AI revealed their Impact Tornado Grenade, which fires on direct impact with something rather than a timer. Booligan's review of the Tornado Grenade can be found here.
After discovering that Green Gas is just propane with silicone added, AI released an adaptor for airsofters to use small propane tanks to fuel their gas powered guns. Many users use propane as their fuel source now, as it is much cheaper, and far easier to acquire. Not to mention, less dangerous than Green Gas. However, propane CAN be flammable, and any gun using is as a fuel source smells of it. The review may be found here.