A button above the trigger allows you to select Low or High speed. Using a 4Ah battery, the EGO string trimmer will run on Low for about an hour. All EGO tools carry a 5-year limited warranty purchased from authorized EGO retailers. There is a 3-year limited warranty on EGO Power+ System battery packs and… Continue reading Ego-ST1520S PowerLoad Cordless String Trimmer Carbon Fiber 15in Tool Only ST1520AS