Endurance Solar Fairy lights are designed for high performance with excellent longevity. Truly beautiful lights that are easy to install (no mains wiring), they recharge themselves during the day from solar power, & automatically switch on for up to 12 hours every night. The powerful 300m Ah polycrystaline solar panel is designed for all UK weather even in winter, & even in the most rubbish weather that the UK can throw at us the panel can be simply detached from the lights & charged via USB (Universal Serial Bus). The solar panel is so efficient it can be even placed in a sunny windowsill indoors & still charge enabling you to have indoor string lights without the need for mains power. The rechargeable batteries are only the very best quality which are not cheap & designed to last a long time, many solar products need the batteries replacing after a couple of seasons. The light strings are made with thick copper wire coated in an anti ageing rubber, so although these lights are more expensive than other solar lights, they are made with the best quality components so they really do work in the UK year round & last for years, hence their name ' Endurance'. The lights come with an 8 function controller, & can be left to turn on & off automatically, or switched on & off independently. Solar panel 2V, 300m A Battery Ni Mh 1.2V, AA 1000m Ah LED spacing 10cm String length 2m to first light, 9.9m of illumination Running time 8-12 hours in summer/ 6-8 hours in winter (Depending on weather & position of solar panel) Functions 8 functions including flash & static; 1. Steady On, 2. Slow Glow, 3. Fast Twinkling, 4. Slow Twinkling, 5. Flashing in Series, 6. Flashing in Reverse Series, 7. Fast Flashing in Series, 8. Slow Flashing in Series, 6. Flashing in Reverse Series, 7. Fast Flashing in Series, 8. Slow Flashing in Series followed by Reverse Series