A shining example. Both in terms of battery life and price.
An ideal entry-level model, the Ledlenser SEO3 comes in green and orange and has an ideal price-performance ratio. The SEO3 runs on regular AAA batteries and on the lowest setting the light can last up to 40 hours1. You focus it with a rotary switch and it is overall very easy to use. It also sits lightly and comfortably on your head. What's more, the headband can be removed and washed.
LED Configuration 1 x Power LED
Luminosity1 MAX 100 lm - MIN 15 lm
Lighting Range1 100 metres
Battery Duration1 MAX 40 h - MIN 10 h
Battery 3 x Micro (AAA) 1.5V
Battery Capacity2 5.63 Wh
Water Resistance IPX6
Head Diameter 29 mm
Weight 105 g