1/2 oz 17% Pepper Spray in Hard Case w/ Black Case 1/2 oz 17% Pepper Spray in Hard Case w/ Black Case At 17% and two million S.H.U., our Street Wise pepper spray is the hottest, most powerful in the world. The potency of this spray enables it to bring down even the most aggressive assailants. With the spray attached to your key ring you'll be able to quickly defend your self without having to waste time looking through your purse or pocket. The holster measures in at 3 and one-half inches x 1 and one-quarter inches.