Biodegradable bb pellets will Disintegrate after some time in your garden or the site you are playing on and are normally non-toxic and safe if your pet eats them, but please check the label if you buy some. Usually, Biodegradable bb pellets will cost a little extra than their non Biodegradable counterparts. One other thing to consider is that they break easier on impact so if you're shooting at someone who has a mesh mask on they can break, and fragments could go through the masks mesh. Some skirmish sites (in woods) and some countries (like Holland) only allow you to use Biodegradable bb pellets so they may be your only choice. They are probably the best bbs to buy if your shooting in your garden as you won't have to bother to pick them up if they annoy you. The 0.20g bb pellets Hear our the standard Weight and most commonly used Airsoft bb pellet for most guns on this site and best used with mid to hi-end electric rifles and powerful gas and spring pistols. A rough guide would be for example bb guns that shoot between 210 to 350 fps to use the 0.20g bbs. Need more info? Click here to see our BB Pellet Buying Guide for more info on our bio bb pellets.