Pro Bike Tool CO2 Inflator Quick & Easy - Presta & Schrader Valve Compatible - Bicycle Tyre Pump for Road & Mountain Bikes - Insulated Sleeve - No CO2 Cartridges Included

I bought this primarily because it was 1) Compact; 2) Had a regulator on the nozzle, which allows you to start/stop the flow of CO2.The first time I used it, it worked like a charm - inflated my flat tire to ~95-100PSI - and still had a bit of CO2 left in the canister. The regulator really helps you control the flow - and possibly have a little extra CO2 left to top it off if you need it later. I'm not sure how long it holds remaining CO2 once opened - my guess is not long - but once opened, the remainder was still in the canister at the end of my ride an hour later.The second time I used it, it appears I may not have sealed the nozzle to the presta valve tightly enough, because when I opened the CO2, the nozzle unseated and all the CO2 was expressed into the air. The rubber gasket that likely seals the valve to presta was stuck on the presta valve and I couldn't get it back into the inflator nozzle. In desperation, I tried to re-inflate again, but without the rubber gasket. Bad idea: it got stuck on the presta valve and ripped the top of it off. Lesson learned: make sure the valve of the inflator is deeply threaded onto the presta valve (which it says to do in the instructions emailed upon purchasing the unit.)I sent an email to Pro Bike Tool asking about the rubber gasket - and within an hour late on a Friday night, I had a response confirming my issue and with no further questions asked, a response that a brand-new unit would be shipped to me immediately.I was really surprised - and impressed with the customer service. Especially since it's highly likely that this was user error on my part.The inflator itself feels really solidly machined - everything is metal. Given my 1st, positive experience using the inflator and the impressive customer service, I'd highly recommend it.

pumping up tires with a manual pump is a pain, and bringing a pump along with you on your bike is a compromise at best. If the pump is small and easy to carry, it takes forever to inflate a tire. If it is big and pumps well, it is too big and heavy. I'm a senior and have discovered that pumping tires is WELL down my list of fun things to do! This handy little pump cures that though!I bought the pump and a box of CO2 cartridges and started looking for something that needed inflation! First stop was my garden cart... it always has chronically underinflated tires. I was able to bring all four up to snuff from flat with two cartridges with some air to spare.I found the cartridges easy to mount and the inflator easy to connect and control with the valve control. The foam sleeve is a MUST as the cartridges gets super cold as the CO2 is dispensed.I next topped off my bike tires and was pleased that I didn't have to break out my beast of a hand pump.I am glad I have this tiny inflator. It is well built, works well and is easy to carry on the bike with a spare CO2 cartridge or two 'just in case'.

UPDATE (10/05/17)=============================After owning this product just over a month, I have no complaints, only praise. Because of its compact size and ease of use, Pro Bike Tool's CO2 Inflator remains a valued part of my bike maintenance program.STICKING VALVE: In my original post I mentioned difficulty getting the valve to open. That issue has NOT repeated; the valve has worked perfectly every time I use the inflator, which is almost every day.CARTRIDGE LIFE: the other question I had regarding this product was how long a cartridge would last once screwed into the inflator. It does appear to lose CO2 over time, but I would call this loss negligible, losing perhaps 10 PSI over a 7-day period. So it's not a perfect seal, but at just under $1/cartridge, it's manageable and acceptable.REVISED RATING: Product continues to live up to its previous 4.75 star review, and as the sticking valve issue has resolved, I revise my rating to 4.9 STARS. HIGH RECOMMEND.ORIGINAL POST========================Disclaimer: I've only owned this product for about 2 hours at the time of this writing. Please check back for progressive updates.SIZE/CONVENIENCE: 5 Stars. Excellent PerformanceI am fanatical about tire pressure, generally, and specifically, for my motorcycle which is my sole transport (Ah, SoCal). So, the first commendation for this product is its size. The whole thing, plus a couple (or 3) extra cartridges fits into a sidepouch of my daypack. Spacewise, VERY economical. Are you a purist bicyclist? The whole setup weighs maybe 7oz (Unit + 1 cartridge) and shares the dimensions of, say, a pack of cigarettes. Please don't smoke.OPERATION: 4 1/2 Stars. Above Acceptable PerformanceEasy to operate, and to understand how to operate. Device mounts to tire (Schrader valve) as advertised (both Bike and Moto tires). Cartridge mounts to device as advertised. Delivers C02 gas to tire as advertised, with a * (see below). Here are my results: A single 16g cartridge took my mountain bike tire from 17psi to 41.5 psi, AND my motorcycle tire from 30 to 36psi. Total psi output from 1 cartridge: about 30 psi. There have to be lots of environmental factors than can grossly affect that result. For instance, the bike tire was inflated indoors/78F while the moto tire was outdoors/100+F. Would that affect performance? Someone out there must have that answer.* The reason the Operation eval only gets 4.5/5 stars is because the valve got stuck in the off position after I swapped in a new cartridge. So tightly closed I was about to go get a pair of pliers to get it to open when it finally gave in to extreme hand pressure. Yet another environ factor mitigating operation? Who knows, but you might want to check back here for updates to see if it is a persisting problem.ADVICE/TRICK: Make sure the cartridge is screwed in fully. I thought I had done so, but was getting a relative trickle of air coming out the valve. In fact, thought cartridge might be spent. So I gave the cartridge another tightening twist, just in case, and upon re-test the air blasted out as one would expect. Word to the wise, and a suggestion for those interested in tweaking air flow delivery.OVERALL: Highly Recommend with a combined rating of 4.75 stars.Look for an update to this review in about 30 days (including, for instance, how long a partially full cartridge lasts while attached to the device when not in use)