Qbicle AIRclub Pump Qbicle Co2 Airclub Seatpost Bracket 27.2 Aly Bk

For the most part this does what it should and looks cool while doing it. I gave it 4-stars because 1. it seems over-priced at $20 (making me think twice about the value of this slight improvement in convenience), and 2. I lost a couple cartridges which simply unscrewed and fell out during the ride. This latter point may be less significant for roadies but more problematic for mountain bikers, like me. How do you keep the cartridges screwed in so tight they do not fall out but are still loose enough that the do not freeze making them difficult to remove when you need them? Solution: Slide a 1-inch section from an old inner-tube over the cartridges banding them together so they can't rotate. I'm sure a rubber band would work fine but the inner tube band is already the perfect size and more durable. I see the price has dropped a couple dollars so my first gripe may get resolved as this product becomes more affordable. Quality is good. I like the bracket and would buy it again.