Institution,, B. S. (1998). Nuts, bihexagonal, self-locking, with counterbore and MJ threads, classifications: 1100 MPa (at ambient temperature)/425°C, 1100 MPa (at ambient temperature)/650°C, 1210 MPa (at ambient temperature)/425°C, 1210 MPa (at ambient temperature)/730°C, 1550 MPa (at ambient temperature)/235°C, 1550 MPa (at ambient temperature)/425°C and 1550 MPa (at ambient temperature)/600°C. Dimensions.. London : British Standards Institution. http://access.bl.uk/ark:/81055/vdc_100104843226.0x000001