I bought this one a few years ago. This type of timing chip is becoming obsolete in North America. The Las Vegas Marathon, Los Angeles Marathon, Honolulu Marathon and Philadelphia Marathon have switched to a disposable paper type timing chip last year. So after 26.2 miles of running, the runner no longer needs to lift up his/her foot for the volunteer to take off the chip from the shoe anymore. The timing chip becomes the souvenir for the runner.
So how about (heavy) rain during the race? Would the paper chip be damaged too?
7,000 runners at the Honolulu marathon last year didn't get their finish time recorded due to heavy rain. I was lucky though. Guess what, they were using this disposable timing device. But the company has since changed the paper to waterproof paper and it is fine now to use.