L630R
Wiring Device-Kellems L630R HWD Twist Lock Receptacle 250 VAC 30 A L6-30R/
This white version is a great alternative to the standard gray model.
Pass & Seymour L630-R Turnlok Single Receptacle 30 Amp 250 Volt NEMA L6-30R
The material is Innovative Composite Technologies, so it won't rust even if you leave it in the rain.