If you'd like a little more information on the DC0, our friend Greg reviewed the light and we've posted it here.
This light is meant to be used. All of our lights include a battery, a cigar box, and our no-questions-asked lifetime warranty. Here are some specs on this light.
Material: 6al-4v Titanium
Pill Material: Copper
LED: 1 Nichia 219c 4000k
TIR (total internal reflection) optic
Modes: ML / L / H (with off-time memory)
Output on High: ~ 500 lumens
Forward Clicky Switch
Cell: 1 14500 ICR Lithium Ion (included)
Weight (without battery): 59g
Driver with constant current control, low voltage warning, and reverse polarity protection