9", 12/3 STW, Locking Cord Adapter, Yellow, Converts 15A-125V Straight Cap To 20A-125V, Standard 15A U- Ground Plug, (NEMA 5-15P), Twist To Lock 20A Receptacle (NEMA L5-20R), Twist-To-Lock Adapters Designed For Use In Construction & Industrial Applications Where Extra Protection & Durability Are Needed, Constructed With Heavy-Duty 12 Gauge Wire & Molded Locking Male & Female Connectors.