.65 Caliber pepper projectiles are the some of the most powerful pepper on the market today for projectiles. The effects on a would be attacker are: 
Burning in throat
Wheezing
Gasping
Dry Cough
Shortness of Breath
Gagging
Inability to breath
 
Giving your an opportunity to move your friends and family out of harm's way or subduing the would be assailant.