McMaster 4627K335 Medium Pressure Iron Pipe Fitting, Plug with External Square Drive, 1 NPT G0329637 Includes molded slots for ID Includes molded slots for ID labels and label holders for content identification Emergency Response Guide Pressure Rating Medium Pressure Shape Cap and Plug Drive Style External Square Fitting Type Plug Fitting Connection NPT Male Pipe Size 1 Construction Solid Pressure Class 300 Body Shape Square Material Iron Maximum Pressure @ Temperature 400 psi @ 72° F Maximum Steam Pressure @ Temperature 300 psi @ 550° F Certification UL Listed Connects To Pipe Class 300 Material Steel For Pipe Material Steel For Pipe Schedule 80 For Use With Air They are for use in noncorrosive environments