Looking for options for REALLY SMALL portable C02 inflators that take threadless cartridges. Currently using a Genuine Innovations Microflate Plus, but it's too large to fit in my new seatbag and my jersey pockets are usually full of other stuff. I've taken a look at the AirChuck, but it only takes threaded cartridges and I have a box full of threadless ones from Canadian Tire I don't really want to get rid of.