The wide range adjustable arm can help to get most suitable angle for lighting. Espcially in Europe right angle is most popular on the market, 40W 60W 2 powers are available.Battery is the heart of sun energy road light determining its life span. The battery can be charged over 2000 times recycle time. If one day 1 times full charge (2000/365=5) it can use for 5 years. We will test all the battery capacity by battery capacity detector to pick up the bad performance battery.