I do most of my work on Christn at night. That and the fact that my garage is not to brilliantly lit, presents a problem, solved incredibly well with this:

It has made my life incredibly comfortable when doing valve adjustments. Not having to sacrifice the use of a hand or hold a torch in my moth, has been an absolute boon.

They are part of my standard kit, when I put on my overall, they land on my head. I switch them on and off as needed, to save the batteries as much as possible. They are good for about 10 hours under the car on a set of new batteries.