DTempleton

The physics of this gizmo are a little confusing, based on this review and nearly everything on line. However, it seems clear that the energy for the impulse comes from the battery, and is *stored* as pressure in the nitrogen tank until used. Nitrogen seems never to be actually released from the canister, so unless there is a seal failure there would never be reason to replace the $177 canister.

If this isn't so, please correct me. I am sure the engineers tried, but it seems likely that some heavier gas such as Xenon might be able to store more energy, possibly in a smaller canister, since it's not being consumed.

Nice review, thanks.