These BBs are safe to use in most airsoft and BB guns but should not be used in precision barrels due to the flat edge over the 1mm exposed powder hole.
These really are exploding BBs which are excellent quality and perfectly round but for a small hole in the side where the sparks fly out from.
By exploding, they don't blow holes in walls or even sheets of paper for that matter (any BB does that!), but they 'crack' on impact with a hard surface much like the Hollywood-style special FX when you see sparking ricochets.
These MUST NOT be used at skirmish sites or fired directly at anything other than a solid surface that does not breathe. When they explode, the plastic shell breaks into tiny little fragments which are ejected at a 'stinging' velocity. So if they hit someone or an animal, they will MOST LIKELY fire fragments into their eyes.
You and anybody else in the area MUST wear eye protection with solid lenses, NOT MESH, as the fragments can enter through the holes in the mesh screen.