Wool fibers are first washed and dried then brushed over to open and separate the fibers. This process is called “carding”. Depending on the carding and brushing preparations, processed wool from the woolen mills may referred to as either roving, slivers or batts.
Slivers are very thick, continuous strands of wool.
Pencil roving is as thick as a pencil and spun without further drafting.
Batts are thick continuous mats that may be used for mattress pads, pillows, quilt fillers or other projects.
Slivers or roving (as typically called) is usually carded commercially into long continuous strands that are 2”-3” thick can be suited for wool spinning but can be used for felting, padding or other craft projects such as for making wooly angels and sheep or forming into “dryer” balls.