The police have been using mace and other pepper spray products since the 90's and the U.S. Postal Service starting using pepper spray in the 1980's and are still using it today.
While stun guns are a good self defense weapon to carry and disable the nervous and muscular system, this effect only lasts for mere seconds or sometimes a few minutes depending on the location and length of time of shock. Whereas the effects of pepper spray, including, pain, temporary blindness and even choking, will last for around 30 minutes, sometimes as long as 2 hours. The longer lasting effect of this self-defense device will give you the most time to get out of a situation when you are being attacked.
If you are looking for a device that will offer you protection without having to get into actual contact with your assailant, then pepper spray should be your number one choice. In order to get the maximum effects of pepper spray, it should be directed at the assailant's face, specifically the eyes which will force themselves shut instantly once they come into contact with pepper spray. Blistering may occur but this is temporary and will wear off but sometimes will cause headaches that can last all day.
Some other Mace Pepper Spray items you may wish to learn about are Pepper Foam which is extremely hard to get off the skin, the attacker usually just smears it around which results in a vicious cycle of pain. Mace Gel is a sticky spray that usually has a longer range of defense and is guaranteed not to rub off.
There is also a Mace pepper gun that you slide a canister into and has a range of 25 feet, You can aim it just like you would any ordinary handgun and can be fired 7 times on one cartridge.
Mace carries sprays, foams and gels with 3 different components: OC, Dye and Tear Gas. You get both the immediate OC effect plus a painful tear gas concentration. The dye paints the assailant so they won't be able to say it wasn't them even if washed off the skin. They will still have markings on the area sprayed the police will be able to identify .
Before you decide to carry pepper spray, you should check to make sure it is legal for you to have it in your possession. Your local gun dealer will know if pepper spray is legal in your state and can probably sell you one of the various styles from a keychain model to a large canister of Bear pepper spray. There are several trusted online services that carry these self defense products.