Sanding station question

Regarding the craftsman sanding station I cleaned up and got running - I ordered the belt that showed it was a 6 x48 inch - I tore it trying to slip it on - the guide rollers were all the way in and it was very tight and all of a sudden ripped in two - Wondering if I was doing something wrong or is there a 50" belt out there ??? I thought all you did was to push the end with the rollers all the way in - slip it on - tighten it back up and call it done...............any suggestions ?
Ill look to see what the next biggest size is I guess.................Thanks Dan

dan there is a lever on the side that shortens the rollers length and you can easily slide on a new one release the lever and your ready to go unless you need to adjust it to run straight with adjustment knob.

Yeah I found adjustments and I had not loosened up the the bolts enough......thanks