Explosion proof and dust-ignition proof|Suitable for use in such areas as refineries, petrochemical plants, and other areas subject to where ignitable gases are present|Unique blade-type, brass contacts exert constant pressure along entire contact surface and provide superior electrical contact|Insulators provide superior dielectric and mechanical strength and lowest arc tracking|Longer plug housing for better gripping and easier plug insertion and withdrawal|Plugs fits any standard non-explosion proof receptacle (NEMA 5-15R, 5-20R or 6-20R) as well as U-Line explosion proof receptacles|A twist of the plug produces audible click to indicate fast make and break of built-in switch contacts|Twisting plug locks it in place and cannot be accidentally pulled out