SY Bicycle Speedometer and Odometer Wireless Waterproof Cycle Bike Computer with LCD Display & Multi-Functions by YS

The whole system is weather resistant and durable. Just make sure you don't lose the O-ring that is used to seal the computer when you install its battery. I suppose the same might be true for the sensor itself although I may have already lost that O-ring. When calibrating the system, the manual has a chart that you can use for different wheel sizes. It also suggests measuring the actual circumference of your wheel. I highly recommend measuring the circumference, as the accuracy was spot-on for me when I did it. Also, my wheel size was a teeny bit larger than any entry on the chart. The computer itself, being wireless is easily detachable and small enough to put in a pocket. I strongly recommend doing that unless you stop or park in highly secure areas. That was how I lost my previous bike computer, within 2 weeks.

Easy to install, precise, all the required modes are there including current time. Automatic start/stop. Everything is included. Choice of colors is a plus too. Won't register speed or distance below 40°F, this is annoying! One day delivery.

The price that it was easy to install and was very straight forward to program. You must read and follow the instructions. I use it to mainly keep track of my speed and distance travelled. Also too I like that I can p program for KM or MILES per hour. Oh one other thing no wires, great.

Item better than described, fast delivery & great price. Very satisfied.

Update: After messing with this thing for several weeks I find it to be completely unreliable. It'll read great one day and the next day it will vary between showing zero MPH and 15 MPH. I don't know if the cell phone that I carry interferes with the wireless signal or what but this thing does not work well at all. What I wrote below was how I felt in the middle of my trials. The physical installation is not difficult - tie wraps and such. No big deal. What is difficult is working out the distances along with the particular configuration of your bike. The distance from the computer to the sensor is critical. You get beyond or even close to the 60cm distance from the computer to the sensor and you will get very erratic readings or no readings at all. Same with the 3mm distance between the sensor and magnet. 3mm is about 1/8 of an inch! I have a trail bike with wide forks. That presented an issue in getting the sensor close to the magnet AND also having the sensor not too far away from the computer. I had to try about 8 or 10 configurations where I finally ended up with the sensor tie wrapped on the INSIDE of the fork up close to the brakes (had to keep within the 60cm distance from sensor to computer) which allowed me to get the sensor and magnet within the 3mm distance as well. Once I got those distances happy and figured out how to mount the sensor in the wide fork spacing, everything worked great! Nice features on the computer and you can tune the wheel diameter to get the mileage distance more accurate.