Hooking up a Holter Monitor:

White: 1st intercostals space, mid-clavicle on right
Black: 1st intercostals space, mid-clavicle on left
Green: Lower right at the last rib, just anterior of the mid-axilary line (ground lead)
Brown: 4th intercostals space, right sternal border
Red: Lower left at the last rib, just anterior of the mid-axilary line