The 3M Company entered the market in the 1960s by creating parallel lay flat cable, widely known as ‘ribbon cable’. In parallel lay flat cables the conductors are laid side by side in their respective insulations along the entire length of cable. The controlled physical dimensions result in good transmission lines. It has good cross talk reduction when driven in either balanced or unbalanced configurations. Parallel lay can replace twisted pair when driven unbalanced except in applications where magnetic immunity is important and can do so at significant cost savings. The ability to decrease cross talk, or minimize grounds to increase signal density, makes parallel lay a very versatile cable. Parallel lay cables come in single colors typically grey or with the individual conductors picked out in rainbow colors to aid identification during termination.