If you have a home that was built in the 60's or 70's you may have aluminum wiring. Aluminum wiring was a trend that was used to lower construction costs. However, this low quality wiring has an increased fire danger. Installing copper pigtails onto aluminum wiring branch circuit wiring helps maximize conductivity between aluminum and copper connections.
Instead of rewiring your home, installing AlumiConn or Twister AL/CU UL listed wire connectors are a more cost efficient method of protecting your home from a potential fire hazard. Aluminum wiring will expand as it heats and contract as it cools making it prone to arc faults. By installing these connections at splice points you can reduce the risk of arcing.