ASTM A420 waa qeexitaanka caadiga ah ee ku-rakibidda tuubooyinka ee bir yar iyo bir bir ah oo loo isticmaalo adeegyada heerkulka hooseeya. WPL6 waa qalabka ugu badan ee loo isticmaalo A420.
Ka sokow Fasalka WPL6, heerka sidoo kale waxaa ka mid ah WPL9, WPL3, WPL3, WPL3, WPL3, Heerkulka Imtixaanka Saamaynta ee -45Flæ, -75¡æ, -100¡æ, -100¡mb, -195¡æ