We are located in the South in San Antonio Texas. All of our lighted items use Commercial lights. These lights if left on 24-7 have an approx. 2 year life span. We do not use the cheap lights that you buy in the grocery store that have an approx 4-5 month life span. Our C7 & C9 lights are rated for 130 v ( volts ) this means that they are also Commercial grade most C7 & C9 lights are rated for 120 v ( most electric companies run 124v so when there is a spike or power serge the filament in the bulb blows but with a 130v the filament stays intact and your light does not go out. We have over 1,000 130v lights on our building and we replace about 100 a year . We have had them in place for 2 years . So for the person who wants to place them on the rafters of their home or company this is surly the way to go.