Zeekio Sock Poi are made of spandex-type material that stretches. They are comfortable in your hand and wear well. The stretchiness of our sock poi make wraps, hyperloops and other moves easier. Included is a light bean bag .Weight can be increased by simply putting a larger ball or beanbag in through the easy access side slot. These Poi can easily accommodate a tennis ball. Unstretched these Sock Poi measure 26". Zeekio sock poi are sold as a pair and comes with bean bag balls for ideal spin and stretch.