This AC WORKS brand adapter L1430630-018 is very durable with a flexible design. It is a NEMA L14-30P to NEMA 6-30R. The NEMA L14-30P is a 30 Amp, 125/250 Volt, 4-prong male plug. The NEMA 6-30R is a 30 Amp, 250 Volt, 3-prong HVAC female connector. The product is heavy-duty STW 10/3 30 Amp copper wire with a 600 Volt Jacket.