Sigma Electric C-500 NM/SE 3/8-Inch Clamp Type Connector, 100 Count Terminates NM Cable or Flexible Cord to a 1/2-in knockout For 14/2 - 10/3 NM Cable or .29-in - .45-in Flexible Cord Tri-combo screws included Zinc die-cast construction Product is UL and CSA listed Sigma Electric