The Surly Disc hub is standard English threaded 1.37" x 24 tpi for a single-speed freewheel. It cannot accommodate a cassette. You can get a solid axle bolt-on version or a quick-release version. Check out the FAQ for more detail about SS hubs.synkronized23 said:How is a SS Hub different from a normal hub? Can I use an SS Hub to run geared? Specifically, I'm looking at a Surly Disc Hub. Any information will be helpful. Thanks.