UNE-EN 2879
Aerospace series - Nuts, anchor, self-locking, air resistant, sealing, floating, two lug, with counterbore, in corrosion resisting steel, passivated, MoS2 lubricated - Classification: 900 MPa (at ambient temperature) / 235 °C (Endorsed by Asociación Española de Normalización in March of 2017.)