IKEA SOMMARLANKE Led String Mini Lantern Lights, 12 Lights, Battery Operated

They use 3 AA batteries and there’s a button that turns them on for 6 hours, then they turn off for 18 hours and turn back on for 6 hours again. Super convenient. Easy to place anywhere since it uses batteries. The length of cord with lights is 90 inches and an extra 60 inches of cord is available, making the full cord length to 150 inches. I use mine outside too.