Valve, Relief, Pressure/Temperature, 3/4", Newer Series Water Heater (Red)The 3/4" valve is used on Atwood water heater models manufactured after February, 2006 and can be identified by the plastic, red, output, thread protector. Older models require a 1/2" valve with the orange thread protector. The 1/2" valve was used on Atwood water heater models manufactured before February, 2006 and can be identified by the plastic, orange, output thread protector. Newer models require a 3/4" valve with the red thread protector. Opens at 150 p.s.i. or 210 deg F. This part is associated with Models: G6A, G6A-2, G6A-3, G6A-6, G6A-6P, G6A-7, G6A-7P, GC6AA-8, CG6AA-8P, GH6-6E, GH6-7E, GH6-8E, G6A-6E, G6A-7E, G6A-8E, G19-2E, G10-3E, GH10-2E, GH10-3E, GCH6A-10E, GC6AA-10E, GC10A-4E, GCH10A-4E, XT Series. | Dometic Valve, Relief, Pressure/Temperature, 3/4", Newer Series Water Heater (Red)