Long story short, this part fits, works, and saved me a bunch of cash. I have had it installed now for a week with no problems. I'll update if I have any.My only gripe is that it is supposedly a fragile part and yet it came rattling around in a bigger box. The box had air cushions, but the part had weasled its way down to the bottom, so it was taking the full brunt of any wayward tosses at the local UPS distribution center. Nevertheless, it seems to work okay still.If you want the juicy details, here you are:One day I started up my car and got the check engine light. I was concerned of course since I know nothing about cars. As you will see, I learned many lessons from this problem. I took it in to the dealer to have them check the light while they fixed an unrelated recall.First lesson: the dealer in town charges $103 just to check the error code and tell you what is wrong. That is applied as a credit towards the overly inflated repair estimate they'll give you.By the way, it was error code P2a00 I think, which is a bad Bank 1 Sensor 1 Air/Fuel sensor (aka o2 sensor). The Fit has two: one on the exhaust manifold, and one on the catalytic converter. This is the one on the exhaust manifold, towards the front of the car. Honda Fits of this type have been known to have problems with their o2 sensors going bad early, so much so that there is a Honda service bulletin about it, but not bad enough to warrant a recall (wat.).So the dealer said that the part would cost $330 and the total estimate was $570! Yowza. No way. I already felt cheated from the $100.Second lesson: You can buy an ODBII code reader here on Amazon for $100 or less, keep it for many years, and save yourself a pile of cash whenever you get a check engine light. Next time I get a light, I'll be getting a scanner instead of bending over at the dealer's.After doing some online checks of the error code, I thought I might be able to do this job. So I ordered this sensor from Auto Parts Discounters on Amazon since it was in stock and would ship right away. They didn't disappoint - I received the part just a few days later, faster than expected. I do have Amazon Prime but ordering the cheaper Prime version would have taken 2 weeks to ship.My main concern was that somehow the Amazon guide for "Does this fit your car?" would be wrong. After all, I know little about cars and have never done any repair job myself. Thankfully, this part fits the 2007 Honda Fit. I did more research to make sure, but was still a bit worried.Third lesson: Go to Advance Auto or another auto parts chain store near you and rent an oxygen sensor socket kit. This will save you from buying one and will be free. Plus you will want the socket in order to have a problem-free repair job.Fourth lesson: Get some PB blaster for the inevitable rusty screws under the hood. Also blast your old o2 sensor with it before to make it easy to remove.Fifth lesson: The Honda Fit's o2 sensor is a pain to get at, but it can be done.Unfortunately, it's in between the engine block and the firewall. So that means it's down on the exhaust manifold in between where the engine is and the interior of the car. You can go at it from below if possible, but we did it from the top. Going at it from the top requires removing the heat shield (3 screws) and then working at a funny angle to get at the o2 sensor (which is on the driver's side of the exhaust manifold).Sixth lesson: Dealers are a ripoff. My dad and I replaced the part in about an hour (if you know you way around a car you can probably do it in 30 minutes or less). I essentially saved hundreds of dollars for a couple hours of research and work.Bonus lesson: Disconnect your battery for a few minutes to reset any error codes and see that check engine light go away after your repair job. Obvious to many, but was not for me until I read about it on the internets.Hope this helps.