If you get one of these, make sure that the black rings that thread into the crankset are tight and you may consider using a thread locker to make sure they stay there.

I used those on my heavy touring bike several years ago for a month long tour. I have to remove both crank arms to fit my bike into the S&S case. But one of the black rings self extracted somewhere in the middle of Iceland. When I went to remove both crank arms, discovered one was missing. That meant I had to remove the other one to move to the other side of the crank when I lacked the proper tools to do that. Since then I now carry a real proper crank arm removal instead of the self extracting crank bolts.