How Much Does A Keychain Pepper Spray Cost

The crime rate in Malaysia increases every year. The robbers are becoming more daring. Rob in broad day light, rob in public places and the worst is they rob and kill too. Snatch thieves are becoming rampant. In this kind of cases, is a pepper spray useful? It is to a certain extend but we need the police to be more alert and do their duty. Thieves, robber, rapist and murderer are very daring because the police cannot catch them. Anyway, I must equip myself and my children with at least a keychain pepper spray. How much does it cost? It is about $5 only. :)