McMaster 4627K334 Medium Pressure Iron Pipe Fitting, Plug with External Square Drive, 3 4 NPT G0845652 Corded Cordless Corded Jet Pressure 3 Corded Cordless Corded Jet Pressure 3 Largest Drill Bit Size 1 in With better strength than our low pressure iron and steel pipe fittings Pressure Rating Medium Pressure Shape Cap and Plug Drive Style External Square Fitting Type Plug Fitting Connection NPT Male Pipe Size 3 4 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