The 7, 14, and 21-ounce balls are the approximate size of a baseball while the 32-ounce ball is the approximate size of a softball. The Sand-Filled Weighted Balls are made of a durable vinyl shell with filler. Resilient and small, these weighted balls were designed to be used in close quarters as tools to improve arm strength and increase arm speed in the throwing motion.

The construction of these Sand-Filled Weighted Balls makes them pliable, squeezable, easy to handle, and ideal for exercises or environments where rebounding is not wanted. Ball firmness can be adjusted by adding or decreasing air volume with an athletic ball inflation needle. The balls are color-coded and available in four different weights: 7 ounce (Red); 14 ounce (Yellow); 21 ounce (Blue) and 32 ounce (Green).