I'm not sure if
all of the Best-branded padlocks use the IC's, but all of the ones that I've seen do. If so, you'll need to pick its control shear line in order to remove the core.
To find out more, you can search around on the site for "Best Interchangeable Core": there's a lot of information about those cores, and some suggestions on how to pick them. Matt Blaze also has some really good photographs of the cores, and an explanation of how they work
on his website. A search for SFIC (Small-Format Interchangeable Core) would probably also yield some good results.
(I hope that helps: half the challenge is often just knowing what to search for!)