You might not use a cross laser often, but it's very handy to have your own once the need arises. 18 volts is what you get with this cross laser.
DEWALT DCE089NG18-XJ 12/18V XR 3 X 360 Green Cross Line Laser - Bare Unit
ITS
Dewalt DCE089NG18 12V/18V 360 Degree Multi Line Laser - Body
Conrad Electronic
DEWALT DCE089NG18-XJ Multi-line laser