Going back to my cycling passion, manual hand pumps to repair a puncture in a tube are still used, but not by many. Since CO2 cartridges came into the picture, why wouldn't you use them? Small, almost idiot proof (OK, I've screwed up a couple over the years), and pretty inexpensive at a bike shop. I read that three 16gm cartridges can fill a Harley tire. So....At the HD shop yesterday, I saw a kit offered there that apparently attaches an air line to a cylinder that has a plug removed, and compression fills the tire. Is this true? Does it work? Cant see why anyone would choose that over the CO2. I see a number of problems that could result from that way of inflating a tire. I am planning a number of long trips and I see the value of carrying one. HD wanted 50 for the air line type, and I saw the CO2 type else where for 30. These kits seem to carry all the same reamers, pluggers, patches, glue ect...... Love to hear pros and cons cause I have no idea what works best out there on the road when you really NEED it to work.