Our dryer balls are made from 100% Romney wool with no additives. No pesticides, no fabric softener - nothing but a hard ball of wool. The beauty of the dryer ball is that it bounces around in your dryer and softens all the clothes. It promotes faster drying and is gentle on all your things. My dryer balls live in my dryer and work on every load of laundry I dry.
Our dryer balls come in packages of four which will work very well for smaller loads. I have ten in my dryer because I tend to hold on to the clothes and do them in larger loads less often. Ten is the current number. I've had to replace several over the years because occasionally one will get loose and the dogs will work on it for several days before I find the remnants. Oops!