Russian balls are hollow juggling balls that are partly filled with sand, salt, grain or other kinds of filling. The filling in the ball fall down to the bottom of the ball when you catch it, giving it a more solid feel. This type of ball also is good for balancing, body rolls and other kind of contact juggling tricks because the filling sitting on the bottom of the ball makes it more stable to balance.

The filling in the ball makes a big difference. Renegade uses micro-glass beads, the glass is very slippery and dense so it flows to the bottom of the ball much more quickly than other materials. Also it does not move up the side of the ball when you roll it, so it is very good for contact juggling, or tricks that require hard catches, or stalls.

When you toss juggle a russain ball, the filling can cause the ball to wobble, from the filling staying on one side of the ball. The wobble effect is less with liquid silicone filled balls, like the sil-x ball and more pronounced with glass bead or other solid fillings. So there is a trade off between the amount of wobble and the increased stability for catching or rolling the ball. In general liquid filled balls are better for toss juggling ( less wobble when thrown) and micro-glass bead balls better for contact juggling (better balance).