Adapter leads, made from some of the contents of my electric bits box.
1) 2.5mm DC power plug to PP3 clip, so I can plug my Dinotte light into my collection of Vistalite Nightstick batteries
2) PP3 clip to 2.1mm DC power socket, so I can plug my Magicshine light into a 6 x AA battery box which I happen to have, filled with six matching AA Nimh batteries I also happen to have.