12 mm Thru x 142 mm 6-Bolt Disc 32 Hole Shimano/SRAM 11 Speed Road Bicycle Rear Hubs
This is hub spacing and is the width of the hub. It must match your frame specifications.
This should correspond to the type of brakes you have on the bike.
The hub drilling is the number of spoke holes. It must match your rim spoke count.
The cassette body type is the type of cassette and number of speeds the hub will accept.