Hubbell Wiring HBL2274 Twist-Lock Convenience Adapter 15 Amp Male End 20 Amp Female End 125 Volt 2-Pole 3-Wire White: Amazon.com: Tools & Home Improvement
HUBBELL, Locking-Blade to Straight-Blade, 15 A, Plug Configuration Adapter - 3D536|HBL21CM28 - Grainger
Hubbell HBL5666VY 15 Amp 250 Volt 2-Pole 3-Wire NEMA 6-15P Yellow Nylon Straight Blade Plug | NorthEast Electrical