This is overpriced in the past... but seems now a decent coupon, perhaps is time to try it.
Seems that the coupon is only for the option 1xAA, but I can prescind the tube for 2xAA (with this tube, is a really awful light), I do not understand why if you add the Tube, the coupon seems not valid. (you can buy tube separately for 3,49 USD)
● The HR20 is a lightweight and multifunctional headlamp, weighting merely 46g
● Utilizing CREE XP-L HI LED in conjunction with copper MCPCB, max 1000Lm output
● Rotatable brightness adjustment to any desired brightness, coping with multiple unexpected accidents
● Built-in Micro USB charging port, the battery in the HR20 can be charged conveniently
● Innovative switch design for easy operation
● Optimized lens and reflector for impact resistance and excellent beam
● IPX-8 standard waterproof (2m) for severe weather
● Advanced temperature control module prevents over-heat