Biodegradable BBs respect the environment in which you'll be playing and evolving. They are also recommended when playing in association. Airsoft balls come in different weights depending on the type of replica used. For example, on a sniper-type replica, it's preferable to use a heavier ball (from 0.28g), so that external elements such as the wind don't have too much influence on the ball's trajectory. For normal use with a standard replica, 0.20g, 0.23g or 0.25g balls are recommended.
