BS EN 4122:2018 Aerospace series. Shank nuts, self-locking, in heat resisting steel FE-PA2601 (A286), silver plated on thread. Classification: 1 100 MPa (at ambient temperature) / 650 $0DC

Silver
Dimensions
Nuts
Fasteners
Marking
Heat-resistant materials
Metal coatings
Aircraft components
Locknuts
Threaded fasteners
Surface treatment
Steels
Designations

Link: BS EN 4122:2018 Aerospace series. Shank nuts, self-locking, in heat resisting steel FE-PA2601 (A286), silver plated on thread. Classification: 1 100 MPa (at ambient temperature) / 650 {$permalink}DC
Source: BSI Standards

BS IEC 60772:2018 Nuclear power plants. Instrumentation systems important to safety. Electrical penetration assemblies in containment structures .

Nuclear fuels
Nuclear-electric power stations
Nuclear power
Transmitters
Nuclear physics
Safety
Energy sources
Health and safety requirements
Nuclear technology

Link: BS IEC 60772:2018 Nuclear power plants. Instrumentation systems important to safety. Electrical penetration assemblies in containment structures .
Source: BSI Standards