G&G bio BBs are a good choice when choosing biodegradable ammunition. Accurate measurements and even surface guarantee that these BBs work in pretty much all guns. G&G bio BBs also decompose rather quickly when exposed to nature after use.
The photo is old, actual color of these BBs is white.
These BBs are safe for the environment. In practice, a BB is biodegradable when it dissolves into water, hydrocarbons and other natural substances during a long decomposition process. Regular plastic BBs take hundreds of years to decompose into microplastics that spread to humans and animals alike. So if your game field only allows biodegradable BBs to be used here is an excellent choice for a little bit greener airsoft games!