fabric widths vary from manufacturer to manufacturer===on fabric.com if you click on a fabric you are interested in the description tells you the width---i don't know if Connecting threads does the same-
but you can find fabric in widths from 36" up to 54" and everything in between- if you are purchasing for a specific it is a good idea to check the width so you can adjust your purchase as needed-
it has nothing to do with the supplier (fab.com/ connecting threads) they purchase it and try to give you accurate descriptions.
fabrics have varied this much for many many years----and is most apparent (to quilters) when they shop at larger stores that carry fabrics for apparel and home decor along with quilting fabrics.
the lqs' generally have fabrics considered specific for quilting and they (generallY) range 42"-44"
but stores that carry fabrics for many uses-not specific - shop for the best deals to offer their customers- and purchase from more/different suppliers than the lqs may use.
best to always check the end of the bolt- and the descriptions to see what you are getting.