In reply to Vanessa Simmons:
In my opinion the co2 inflator is next to useless.
I was stranded and used mine but I had to partially inflate to find the leak, fix the leak, inflate again, have the fix fail, re fix the leak, inflate again but no, I have used all 4 gas canisters and spend the next 20 mins with a push bike pump.
Now I have a tiny compressor (£16 on ebay) and a power socket.
Last puncture was a doddle and the socket (mounted on my bars, £6 on eBay including bracket) doubles up for charging my phone.