What do you mean by "actually works"? Most locks "work" Put a cable or chain in the mix and that will lock it to whatever.. I use a cable and pad lock to secure my propane tanks, but have not worried too much about my spare on the back of the trailer.
Can either of those be cut? Sure... I guess I am just keeping honest people honest, but if someone wants something bad enough and they are willing to go thru some effort and risk not getting caught, then I guess that's where these things fail.
I have had my battery grow legs and walk away after leaving it on the trailer at my house.. Now, I just remove it after each trip.. Sure, it's a PITA.. But, it's easier than trying to secure it, because it's hard to wrap a chain around a battery.
๐Good luck!
Mitch
2013 F150 XLT 4x4 SuperCab Max Tow Egoboost 3.73 gears #7700 GVWR #1920 payload. 2019 Rockwood Mini Lite 2511S.