Handmade practice poi stretch fabric with soft 80g bean bag, featuring an inconspicuous opening to swap out the weight. Length can be adjusted!  Use a bolt or an unsharpened pencil to push the  fabric out the larger hole, working the washer out to release the pointed end. Shorten as desired. Then fold the end over the washer, and carefully work it back into the larger hole.  Push the washer as deep as possible to secure the Sock.  You can also tie a knot.  

Spandex fabric