Review on JACO Lightning Presta Schrader Valves by Dustin Keller

I read about this tool and was impressed that it's well built and works with both Schrader and Presta valves ( I was mostly worried about Presta for my bike and inflating/mounting tubeless tires). What frustrated me was that I really only wanted/needed one cartridge, but the listing was for two cartridges, so it was either that or nothing. Consequently, the price was about double what I should have paid. But for a great product I would (and maybe share another one with a friend)! I found the cartridge a bit difficult to use. If there were easily accessible guides, I might know the best way to use them. (The manufacturer directed me to a video on the product page, although it's more promotional than educational. Although it reinforces the idea of screwing the cartridge onto the valve after the sleeve is locked.) * Switching between Schrader and Presta is laborious . and hard on the fingers. I seem to have to hold a narrow treadmill to keep it from spinning when rotating the outer barrel relative to the inner barrel to switch S to P. The manufacturer suggested that it would be easier to grab the blue sleeve when I slide it out/latch the inner barrel. I've tried it and it's worked on a few, but the polished combs are still not that easy to come by; I think a fluted surface would help a lot. Or maybe a button or something else I could press to lock the inner cylinder in place when I turn the blue bushing. * My Presta valve lock doesn't seem secure at all. After you put the valve on and moved the outer cylinder outward towards the valve, it seemed tight but not tight and it seemed like air was flowing through. After I contacted the manufacturer, he suggested that I try to fix the problem and then abandoned the thread. it seemed safer, although I haven't tried it under pressure yet.) * It would help if the cartridge could rotate when bent 90 degrees. Given that it threads onto the end of the tubing and tubing doesn't rotate naturally, it was inconvenient to adjust the chuck to the position/orientation I needed to secure it to the shank. If I've missed some important instructions and it really is a lot easier to use than what I've experienced, I'd be happy to hear about it (the manufacturer gave some advice when I contacted them). I like the flexibility of being able to use a Schrader or Presta, but for those buying this primarily for use with Presta valves I might be more inclined to recommend a bike pump style combo inflator and cartridge. My inflator came with a head that works passably (not very well) with Schrader valves, so my motivation was to use it on Presta bike tire valves. When I approached the manufacturer with questions and concerns, the gentleman was very nice and helpful. comments and ideas. + for support!