The 8K Cylindrical Lock meets or exceeds the following standards: Certification ANSI A156.2 Series 4000, Grade 1 as certified in Builder Hardware ManufacturersAssociation directory ascomplying with this standard. (Formerly FF-H-00106C Series 161.) Underwriters Laboratories Listed by Underwriters Laboratories for use on 3 hour, A label single swinging doors. GYJT Builders Hardware-Single point Locks or Latches.